Precious Metals Glossary A–Z

The 20-Mark gold coin is a circulating coin of the German Empire (1871–1915) made of 900 gold with a fine weight of 7.168 grams. It qualifies as investment gold and is VAT-exempt at purchase.

333 gold is a gold alloy with a fineness of 333 parts per thousand (33.3%), corresponding to 8 carats, used mainly in the jewellery industry.

375 gold denotes a gold alloy with a fineness of 375 parts per thousand (37.5%), known in the UK and other English-speaking countries as 9-carat gold and used mainly in jewellery.

585 gold is a gold alloy with a fineness of 585 parts per thousand (58.5%), corresponding internationally to the 14-carat standard and widely used in jewellery.

750 gold denotes a gold alloy with a fineness of 750 parts per thousand (75.0%), corresponding to 18 carats, and is the most-used quality in the jewellery and watch industry.

800 silver is a silver alloy with a fineness of 800 parts per thousand (80%), widespread above all in continental European tableware and cutlery.

835 silver is a silver alloy with a fineness of 835 parts per thousand (83.5%), particularly typical of continental European cutlery and jewellery of the 19th and early 20th centuries.

900 gold denotes a gold alloy with a fineness of 900 parts per thousand (90%), corresponding to 21.6 carats – a historically important standard for European and American circulating coins.

916 gold denotes a gold alloy with a fineness of 916.6 parts per thousand (22 carats), used worldwide above all for high-quality jewellery and investment coins.

The acid test is a chemical method for determining the fineness of gold and silver alloys, in which test acids produce a characteristic colour reaction on the metal surface or on a touchstone.

An alloying metal is a base or precious metal added to a precious metal in a defined quantity to deliberately alter hardness, colour, melting behaviour or other properties.

Affinage denotes the industrial cleaning and processing of raw precious metals to trade- or investment-grade fineness.

All-in Sustaining Costs (AISC) are a standardised metric of the gold-mining industry that captures all the costs required to maintain a mine's current production capacity on an ongoing basis.

Allocated gold refers to physical gold that is individually assigned to an owner, stored separately and does not appear on the custodian's balance sheet.

Allocation refers to the deliberate division of a portfolio across different asset classes - including precious metals - in order to bring risk and return into a desired balance.

An alloy is a mixture of a main metal and one or more additive metals (alloying metals), created deliberately to give it altered physical or chemical properties.

A historic gold-extraction process in which liquid mercury dissolves gold and silver out of ore and binds them as an amalgam, which is then separated by heating.

The American Buffalo is the only official gold coin of the USA with a fineness of 999.9/1000 (24 carat), minted by the United States Mint since 2006.

The American Eagle is the official bullion coin of the United States, minted since 1986 in gold, silver, platinum and palladium and among the most traded investment coins worldwide.

The UK Money Laundering Regulations require precious-metal dealers above certain thresholds to identify their customers and report suspicious transactions.

Aqua regia is a strongly oxidising acid mixture of concentrated hydrochloric acid and nitric acid (3:1) that is the only single liquid reagent able to dissolve the precious metals gold and platinum.

Argor-Heraeus is one of the world's leading refineries and precious-metal processors, based in Mendrisio (Switzerland), known for the highest purity standards and the Kinebar hologram.

The ask price is the price at which a dealer or market maker sells a precious metal — that is, the lowest price at which buyers can immediately buy in the market.

An assay certificate is an authenticity document issued by an accredited testing body that bindingly confirms the fineness, weight and identity of a precious-metal bar.

The atomic number states the number of protons of an element in the periodic table, while the atomic weight (relative atomic mass) describes the average mass of its atoms in atomic mass units.

Munze Osterreich AG is Austria's state mint, based in Vienna and the issuer of the world-renowned Vienna Philharmonic.

The avoirdupois ounce (av. oz) is the mass unit commonly used in everyday Anglo-American life, equal to exactly 28.349523125 grams, and therefore differs markedly from the troy ounce used in the precious metals trade at 31.1035 grams.

Backwardation describes a market situation in which the spot price of a commodity is above the futures price – a signal of acute physical scarcity.

The bid price is the price a dealer or market maker is willing to pay for a precious metal – that is, the buying price from the seller's perspective.

A bonded warehouse is a state-approved facility in which goods can be stored outside the duty point, so that no import duty or import VAT falls due while the goods remain there.

Bretton Woods refers to the international monetary system established in 1944 that pegged the US dollar to gold and is named after the venue in New Hampshire.

The Britannia is a state bullion coin from The Royal Mint (United Kingdom), available in gold and silver with a fineness of 999.9 ‰ and 999 ‰ respectively.

Britannia silver refers to a silver alloy with a fineness of 958 ‰ (95.8%), introduced in England in 1697 as a higher standard alongside sterling silver (925 ‰).

Collective term for British bullion coin series from The Royal Mint, issued in themed releases that combine investment value with high collector potential.

Broken gold refers to damaged, deformed or incomplete gold items that no longer serve as jewellery or usable objects and are primarily destined for the melting process.

A state-minted coin that serves primarily as a precious-metal investment and whose value is based on the current metal price (spot) plus a premium.

The buying price is the price a dealer or refinery pays a private seller to purchase precious metals - it is always below the current spot price.

By-product mining refers to the recovery of a precious metal as a secondary product during the extraction of another, primarily targeted raw material.

C. Hafner is a German precious-metal refinery and semi-finished products manufacturer founded in Pforzheim in 1850, which refines gold, silver and platinum-group metals and produces certified bars and semi-finished products for industry and the jewellery trade.

The COMEX (Commodity Exchange) is the world's most important futures exchange for gold and silver futures and the leading price reference market for physical precious metals.

Carat (abbreviation kt or ct) is the traditional unit of measurement for the gold content of an alloy: 24 carat corresponds to pure gold (999‰ fineness, highest trading purity 999.9‰).

The metric carat (ct) is the legal unit of weight for diamonds and other gemstones and equals exactly 0.2 grams.

The cash limit on gold purchases determines the amount above which dealers must verify and document the identity of the buyer under the UK Money Laundering Regulations.

A cast bar is produced by pouring molten precious metal into a mould, which after cooling leaves a characteristically rough, slightly irregular surface.

A catalytic converter is a vehicle exhaust-cleaning system that uses platinum-group metals (platinum, palladium, rhodium) to convert harmful combustion residues into non-toxic compounds.

Central bank purchases refer to the acquisition of gold reserves by national central banks to strengthen currency reserves and as a strategic hedge against currency and systemic risks.

A precious metal bar firmly sealed in a tamper-evident plastic holder (blister) and carrying a printed authenticity certificate from the refinery.

The coin size check measures a coin's diameter and thickness with callipers or a gauge and compares the values with the official minting specifications, in order to expose counterfeits by their deviating dimensions.

The coin weight check is a simple, non-destructive method for verifying the authenticity of precious-metal coins, comparing the actual weight against the manufacturer's official specified weight.

A CombiBar (tablet bar) is a pre-scored precious-metal bar that can be broken along stamped break lines into smaller individual one-gram pieces, without tools and without loss of weight.

Conflict gold refers to gold mined in war or crisis zones, the proceeds of which are used to finance armed groups or human-rights abuses.

Contango describes a market situation in which the futures price of a commodity is higher than the current spot price.

Copper (Cu, atomic number 29) is a reddish transition metal with outstanding electrical and thermal conductivity, regarded as the oldest metal deliberately used by humans and today an indispensable industrial raw material.

Corrosion resistance is the ability of a material to withstand chemical attack from moisture, oxygen, acids or other environmental influences permanently, without significantly altering its surface or structure.

A crisis currency is an asset regarded as particularly stable in value during phases of economic or political instability and therefore in especially high demand.

When precious metals are transported across borders, cash-declaration duties apply above GBP 10,000, along with import VAT and customs rules when entering the UK from abroad.

Cutlery silver refers to solid silver cutlery with a fineness of at least 800 per mille (80%), which was especially widespread in bourgeois and aristocratic households in the 19th and early 20th centuries.

A hydrometallurgical process for extracting gold in which crushed ore is treated with a dilute sodium cyanide solution to bring gold selectively into solution.

The density of a substance indicates how much mass is contained per unit of volume, and is a central authenticity feature for precious metals.

A non-destructive method for testing the authenticity of precious metals by measuring specific density according to Archimedes' principle.

Dental gold is the gold alloy from dental restorations such as crowns and bridges — usually with a fineness between 750 and 900, often with valuable additions of platinum and palladium.

Dental gold refers to precious-metal-bearing dental alloys used in dentistry for crowns, bridges and inlays, which on recycling yield valuable precious metals such as gold, platinum and palladium.

Diamagnetism describes the weak repulsion of a material by an external magnetic field; gold is diamagnetic and is therefore not attracted by magnets.

Diversification refers to spreading capital across different asset classes, regions or currencies in order to reduce the overall risk of a portfolio.

Doré bars are semi-refined raw bars of gold and silver, cast directly at mines or smelters and subsequently processed to fine-metal quality at a refinery.

A historic European gold coin with a fineness of 986/1000 (23.6 carat), minted since the 13th century as Europe's most important trade currency.

Ductility refers to a material's ability to deform plastically under tensile stress without breaking.

Electrical conductivity describes how well a material conducts electric current, and in precious metals it is an important quality characteristic for industrial applications.

The enthalpy of fusion is the amount of energy a substance must absorb to change from the solid to the liquid state at its melting point, without changing its temperature.

Euwax Gold II is a physically backed gold ETC of Boerse Stuttgart that securitises a direct claim to delivery of real gold. It is a German-listed product; UK investors are subject to UK Capital Gains Tax rules on any gains.

The FIFO principle (First In, First Out) determines that, for tax purposes, when precious metals are sold the units acquired first are always deemed to be sold first.

The Fear and Greed Index is a composite sentiment indicator that measures, on a scale from 0 (extreme fear) to 100 (extreme greed), how strongly fear or buying euphoria is driving current market behaviour.

Fine gold denotes gold with a fineness of at least 999 parts per thousand (999 ‰), i.e. a purity of 99.9 per cent or higher.

Fine gold content indicates the proportion of a gold alloy that consists of pure gold, expressed in parts per thousand (per mille) or carats.

Fine weight indicates the actual amount of pure precious metal in a bar, coin or piece of jewellery – regardless of the total weight of the object.

Fineness indicates how much pure precious metal is contained in an alloy – expressed in parts per thousand (e.g. 999) or in carats (e.g. 585 = 14 carat).

The fineness stamp is an officially or manufacturer-applied marking on precious-metal articles that indicates the proportion of pure metal in parts per thousand (‰) or in carats.

The spot price is the continuously traded market price for immediate delivery, whereas the fixing is a reference price set only once (or twice) a day.

A future is a standardised forward contract that obliges buyer and seller to deliver or take delivery of a fixed quantity of a precious metal at a price agreed today for a future date.

Gold (chemical symbol Au, atomic number 79) is a yellow, corrosion-resistant precious metal that has been used for millennia as a store of value, a monetary metal and a functional material.

A US legal order of 1933 that forced private individuals to hand over gold to the Federal Reserve and banned private gold ownership for around 40 years.

A gold bar is a standardised piece of fine gold with a defined weight and fineness that serves as a physical investment form and an internationally recognised store of value.

The denomination of a gold bar describes its standardised weight and largely determines premium, liquidity and suitability for various investment strategies.

A gold ETF (exchange traded fund) is an exchange-traded fund that tracks the gold price and allows investors to participate in its performance without owning physical gold.

Gold hammered or rolled into wafer-thin sheets, used in gilding, arts and crafts and food processing.

Gold coins of the German Empire (1871–1915), struck in 900 gold (crown gold), today classed as VAT-exempt investment gold.

Gold mine hedging is the practice by gold producers of selling future output through forward contracts at a fixed price in order to protect themselves against falling gold prices.

A gold nugget is a naturally formed piece of native gold that comes directly from rock or river sediment and has not undergone an industrial smelting process.

Gold plating is the application of a thin layer of gold onto a base or precious metal, glass or ceramic to improve appearance, corrosion resistance or electrical properties.

A gold savings plan is a regular investment model in which a fixed sum of money is invested at set intervals in physical gold or gold-based securities.

A monetary system in which the value of a currency is fixed to a defined quantity of gold.

The gold-silver ratio indicates how many ounces of silver are needed to buy one ounce of gold – a popular indicator for the relative valuation of the two metals.

A trading strategy in which investors swap gold for silver (or vice versa) when the price ratio of the two metals reaches historically extreme values.

The grain (abbreviation: gr) is the smallest unit of the troy weight system and is exactly equal to 0.06479891 grams.

The gram (unit symbol g) is the base unit of mass in the International System of Units (SI) and the most widely used weight unit in the precious metals trade worldwide.

Granules are small, irregular grains or beads of precious metal produced by pouring molten metal into water, used mainly as an industrial and processing material.

Green gold is a gold alloy with a high silver content that gives the metal a characteristic greenish-yellow hue.

The gross weight is the total weight of a precious metal item including all alloying components, before deducting impurities or additives.

A hallmark is an official or trade test mark that permanently and tamper-resistantly certifies the fineness and origin of a precious metal item.

A magnifier with typically 10x to 30x magnification, used to examine fineness stamps, hallmarks and minting features on precious metal coins and bars.

Heraeus is a German precious metals company based in Hanau that is one of the world's leading refineries and bar manufacturers and is recognised as an LBMA Good Delivery refiner.

The holding period is the length of time between the acquisition and disposal of an asset. In the United Kingdom it determines, together with the annual exempt amount, how much Capital Gains Tax is due on any gain.

In the United Kingdom there is no minimum holding period after which gains from precious metals become tax-free; instead, gains on disposal are subject to Capital Gains Tax above the annual exempt amount, unless the item is a UK legal-tender coin from The Royal Mint.

Home storage refers to the physical safekeeping of precious metals by the owner themselves — in a safe at home, in a bank safe-deposit box or at another self-chosen location.

The ice melt test exploits the exceptionally high thermal conductivity of silver to distinguish genuine silver from fakes: an ice cube melts noticeably faster on a real silver coin or silver bar than on any other metal.

Identity verification is the legally required checking of a customer's identity when buying or selling precious metals above certain cash thresholds under the UK Money Laundering Regulations.

Industrial gold refers to gold used in technical applications – especially in the electronics industry – rather than for investment or jewellery.

Industrial silver refers to silver used as a raw material in technical and industrial applications, as opposed to investment or jewellery silver.

An inflation hedge is the property of an asset to preserve or increase the real purchasing power of the invested capital even when the price level is rising.

The intrinsic value (also material value) of a precious metal object is the pure market value of the fine metal it contains, calculated from fine weight times the current spot price.

Investment gold is tax-privileged gold (bars and certain coins) whose purchase is exempt from VAT in the UK and the EU.

Iridium (Ir) is a silvery-white platinum group precious metal with one of the highest densities of all elements (22.56 g/cm³, just behind osmium) and exceptional corrosion resistance.

Jewellery gold refers to gold alloys used to make jewellery, indicated by their fineness in carats or in parts per thousand.

The Kangaroo (officially: Australian Gold Nugget) is an Australian gold coin with 999.9/1000 fineness, minted by The Perth Mint since 1986 and one of the most traded bullion coins in the world.

A kilo bar is a standardised precious-metal bar weighing exactly 1,000 grams (1 kg), produced for gold, silver and other precious metals in cast or minted form.

The Krugerrand from South Africa is the best-selling gold investment coin in the world – 22 carat, with exactly one troy ounce of fine gold in the one-ounce variant.

South Africa strikes the Krugerrand in four set weights — 1 oz, 1/2 oz, 1/4 oz and 1/10 oz — every one of them sharing the same 916.7/1000 fineness (22 carat).

The LBMA Fixing is a reference price for gold and silver set twice daily in London, used worldwide as a binding benchmark for trading transactions, mine contracts and financial products.

The LBMA Good Delivery standard is the globally recognised quality norm for tradeable gold and silver bars in the institutional wholesale market, setting minimum requirements for fineness, weight, shape and the refinery of origin.

The Libertad is Mexico's official investment coin in gold or silver, struck by the Casa de Moneda de Mexico and recognised worldwide as a bullion coin.

The London Fix is a reference price for gold, silver, platinum and palladium set twice daily, coordinated by the LBMA and used worldwide as the settlement basis for physical precious metal transactions.

The Lunar Series is a collection of gold and silver investment coins struck annually by the Perth Mint (Australia) with a changing motif of the Chinese zodiac sign.

The magnet test checks whether a precious metal reacts to a strong magnet - genuine gold, silver and platinum are not magnetic and are not attracted.

The magnetic balance uses the Lenz effect of the metal-specific diamagnetism values to distinguish genuine gold and silver bars or coins from magnetic fakes.

The Maple Leaf is a bullion coin struck by the Royal Canadian Mint in gold, silver, platinum and palladium with a fineness of 999.9/1000 (gold and silver), which is legal tender in Canada.

The VAT margin scheme is a special value-added-tax procedure under which dealers charge VAT only on their trading margin (the difference between purchase and sale price), not on the full sale price.

Medals are struck or cast metal discs with no legal-tender status, produced from precious metals as commemorative, award or collector's pieces.

The melting point is the temperature at which a substance changes from the solid to the liquid state under standard pressure, without its temperature changing during melting.

Mine production describes the total quantity of precious metal recovered from ore through mining, where the ore grade and the economic minimum content (cut-off) determine which material is extracted at all.

Shares in companies that mine precious metals or other commodities, offering a leveraged stake in the price performance of the respective metals.

A mint is a state-authorised or state-operated facility that strikes or casts coins and bars from precious metals to defined weight and fineness standards.

A mint mark is a small symbol or letter on a coin that uniquely identifies the issuing mint.

A minted bar is a precious-metal bar produced by mechanical minting with a smooth, dimensionally precise surface and stamped information such as fineness, weight and maker's logo.

Mohs hardness is a dimensionless figure on a scale from 1 to 10 that describes a mineral's resistance to being scratched by a harder material.

Japanese unit of weight from the traditional shakkanho system, used today mainly in the pearl trade, equal to exactly 3.75 grams.

Nickel silver is a silvery copper-nickel-zinc alloy containing no silver at all, historically used as a silver substitute because of its appearance.

Nickel white gold is a gold alloy in which nickel serves as the primary whitening metal to give yellow gold a silvery-white colour.

Numismatics is the study and collecting of coins, medals and related means of payment, whereby collector coins derive their value not solely from their metal content but substantially from historical significance, rarity and minting quality.

The opportunity cost of gold is the foregone return that would arise if the capital tied up in gold were instead invested in interest-bearing or higher-yielding assets.

The ore grade indicates how many grams of a precious metal (e.g. gold or silver) are contained per tonne of raw ore, and is the most important metric for assessing the economic viability of a mine.

Osmium (Os, atomic number 76) is the densest naturally occurring element on Earth and belongs to the group of platinum metals.

The troy ounce is the international standard unit for precious-metal prices and equals exactly 31.1034768 grams.

An over-the-counter cash deal is the purchase or sale of precious metals, securities or other assets for cash at the counter ("across the desk"), without recording the identity of the buyer.

PAMP Suisse is a Swiss precious metals refinery founded in 1977, based in Castel San Pietro, that ranks among the most renowned and most widely distributed bar producers in the world.

Palladium (Pd, atomic number 46) is a silvery-white platinum-group precious metal used above all as a catalyst in vehicle exhaust systems and in the electronics industry.

A palladium coin is a minted coin made of palladium with a defined fineness, acquired as an investment vehicle or collector's item.

Palladium white gold is a gold alloy in which palladium, as the principal alloying metal, gives the gold its characteristic silvery-white colour.

The Gold Panda and Silver Panda are official investment coins of the People's Republic of China, issued annually by the China Gold Coin Corporation since 1982 (gold) and 1983 (silver) respectively, distinguished from other bullion coins by their changing panda bear motif.

Paper gold refers to gold financial products such as ETFs, ETCs, futures or certificates that track a gold price without the holder acquiring direct ownership of the physical metal - even if individual products (e.g. Xetra-Gold) securitise a right to delivery.

The pennyweight (dwt) is a unit of weight in the troy system that equals 1/20 of a troy ounce and is used above all in the Anglo-American jewellery and goldsmithing trade.

Per mille (‰) states the fineness of a precious metal as a thousandths share of the total mass and is the legally binding designation on bars and coins.

The Perth Mint is Australia's state minting institution, founded in 1899, and is regarded as one of the world's most renowned refineries and minting facilities for investment gold, investment silver and platinum.

Silver used as a conductive paste in solar cells to conduct away current, today representing the single largest industrial use of the metal.

The ping test is a non-destructive authenticity check that uses the characteristic ringing sound of a coin when lightly tapped to distinguish genuine precious-metal coins from counterfeits.

Platinum is a rare, silvery-white precious metal of the platinum group with atomic number 78, regarded as one of the most valuable metals on Earth due to its exceptional corrosion resistance, catalytic properties and industrial versatility.

A platinum coin is an investment or collector coin struck from platinum with a fineness of at least 999.5/1000 (Pt 999.5), issued by state mints worldwide.

Platinum group metals (PGMs) are six chemically related transition metals – platinum, palladium, rhodium, iridium, osmium and ruthenium – distinguished by exceptional corrosion resistance, high melting points and catalytic properties.

Pound-cost averaging describes the phenomenon whereby regular purchases of an asset with a constant sum automatically lead to a lower average price than the arithmetic mean of all the individual prices.

Precious metals are a group of chemical elements distinguished by their high resistance to corrosion and oxidation, which occur in nature predominantly native — that is, in pure metallic form.

Precious metals are metals with a standard electrode potential significantly more positive than that of the hydrogen electrode, which means they do not react with water, oxygen or most acids under normal conditions.

With a precious metal savings plan, you regularly buy gold or silver for a fixed amount - pound-cost averaging smooths out the price fluctuations.

The premium is the mark-up over the spot price that buyers pay in addition to the pure metal value when acquiring physical precious metal products such as coins or bars.

The premium (agio) is the amount by which the selling price of a precious metal coin or bar exceeds the current metal value (spot price).

Primary production refers to the extraction of precious metals directly from the ground through mining, as opposed to secondary recovery from recycled material.

A private sale transaction occurs when a private individual disposes of an asset – including physical precious metals – at a gain; in the United Kingdom such gains may be subject to Capital Gains Tax.

Proof denotes the highest quality grade of coin striking, recognisable by mirror-smooth fields and frosted, matt designs.

The Rand Refinery is the largest integrated gold refinery in the world and the maker of the Krugerrand, the best-known gold bullion coin on earth.

The real interest rate is the nominal interest rate adjusted for the rate of inflation, and indicates the actual change in purchasing power that an investment delivers.

Recycling of precious metals refers to the recovery of gold, silver, and platinum group metals from scrap material such as jewellery, electronic waste, and industrial residues through chemical or thermal processing methods.

A gold alloy carrying a substantial share of copper, red gold takes on a distinctive reddish, warm bronze-like colour thanks to that copper.

A refinery separates precious metals from scrap gold, industrial waste and ores and processes them into high-purity fine metal.

The reflectivity (reflectance) of a metal indicates what proportion of the incident light its surface reflects back, and is responsible for the characteristic metallic lustre of gold, silver, and other metals.

Responsible Gold refers to gold that has been mined and traded in accordance with ethical, social, and environmental minimum standards along the entire supply chain.

Rhodium (Rh) is a silvery-white platinum group precious metal used primarily as a catalyst in vehicle exhaust systems and for surface finishing, and is among the rarest and most expensive metals on Earth.

An electroplated layer of rhodium applied to jewellery or coins that improves lustre, scratch resistance, and tarnish protection.

Rolled gold is a base-metal core (usually brass or copper) that is mechanically bonded to a thick layer of gold by hot rolling – in contrast to electrolytic gold plating.

Rose gold is a gold alloy with a characteristic pink to reddish hue that arises from a deliberate copper content.

The Royal Canadian Mint (RCM) is Canada's national mint and one of the world's most respected precious-metal institutions, renowned for the Maple Leaf and for the highest purity standards.

The Royal Mint is the national mint of the United Kingdom and one of the oldest continuously operating mints in the world, renowned for bullion coins such as the Britannia and the Sovereign.

Financing companies that provide mines with capital up front and in return obtain the right to buy future precious-metal production at a pre-agreed price or in exchange for a revenue-based royalty.

Ruthenium (Ru) is a rare platinum-group metal with exceptional hardness and corrosion resistance, used chiefly in the electronics industry and as an alloying additive.

A safe haven is an asset that retains or increases its value during periods of economic or political uncertainty, while other asset classes fall.

Scrap gold refers to used or damaged gold items - jewellery, dental gold, coins and industrial residues - that are melted down and refined to recover the fine gold content they contain.

Scrap silver refers to used silver from jewellery, cutlery, coins or industrial products that is melted down or reprocessed as a raw material.

Seasonality in the gold market refers to recurring, calendar-related patterns in the gold price that arise from cyclical demand fluctuations in key regions.

Urban mining refers to the targeted recovery of precious metals and other valuable materials from electronic waste, end-of-life devices and industrial waste streams as a complement to primary mining.

The dealer price is the price at which a precious metals dealer sells a product to the buyer – it is always above the spot price and includes minting or refining costs, the dealer margin and, where applicable, VAT.

Semi-precious metals are metals that show a certain resistance to corrosion but do not possess the full chemical resilience of the precious metals.

A unique identification number engraved or stamped by the manufacturer on precious metal bars, enabling traceability, authenticity testing and certificate matching.

Sigma Metalytics refers to a product line of portable testing devices that use electromagnetic induction to measure the resistivity of precious metals and thereby reliably expose counterfeits.

Silver (Ag) is a bright white precious metal with the highest electrical conductivity of all elements and is used both as an investment metal and in industry, photography and medicine.

A silver bar is a standardised semi-finished product made of fine silver (at least 999/1000) that serves as a physical investment form for private and institutional investors.

Silver coins as circulating money were state-minted means of payment made from silver alloys that dominated everyday monetary transactions for centuries, until rising silver prices forced their withdrawal and replacement by coins made from base metals.

Solid silver cutlery is made entirely of a silver alloy, whereas plated cutlery carries only a thin silver layer on a base-metal core.

A silver ETF (Exchange Traded Fund) is an exchange-traded fund that tracks the price performance of silver, without investors having to buy or store physical metal themselves.

The silver ounce is the international standard unit for silver trading and refers to one troy ounce of silver with a weight of 31.1035 grams.

The tax-related surcharge on silver purchases refers to the portion of the price that buyers pay above the pure metal value, because investment silver - unlike investment gold - is subject to VAT.

The Somalia Elephant is an annually redesigned silver bullion coin that, despite its name, has been officially issued by the Republic of Rwanda since 2016.

The Sovereign is a British gold coin with a fineness of 916.7‰ (22 carat) and a fine weight of 7.3224 grams, minted since 1817 and widespread worldwide as a classic bullion coin.

Specific gravity (also: relative density) indicates how much heavier a substance is compared with water (density 1.0 g/cm³) and is one of the most reliable metrics for testing the authenticity of precious metals.

The spot market is the market for immediate delivery of precious metals at the currently valid spot rate.

The spot price is the current market price for the immediate delivery of one troy ounce of a precious metal - the basis of almost all buying and selling prices.

The spot rate is the currently valid market price of a precious metal for immediate delivery and settlement, also known as the spot price.

The spread is the difference between the buying price (bid) and the selling price (ask) of a precious metal and represents the dealer's implicit trading margin.

Sterling silver is a silver alloy containing 92.5% fine silver (925/1000) — the standard for cutlery, jewellery and many collector items.

The streak test is a classic chemical method for determining the fineness of gold alloys, in which a metal streak drawn on a touchstone is compared with acid solutions of known concentration.

The strike price is the standardised reference price of a precious metal, on which premiums, dealer margins and options contracts are based.

The interplay of supply (mine production, recycling, central-bank sales) and demand (jewellery, industry, investment) largely determines the precious-metal price.

Two fundamental mining methods in which ores are extracted either in open-pit surface mining (near the surface) or in underground mining (in deep tunnels and shafts).

Fairtrade Gold is certified gold from artisanal and small-scale mining that meets minimum social standards, environmental requirements and a binding Fairtrade premium on top of the market price.

The tael is a traditional East Asian unit of weight for precious metals, whose exact weight varies by region between roughly 37.4 g and 37.8 g.

Tarnishing refers to the surface discolouration of metals through chemical reaction with sulphur compounds or oxygen from the surrounding air.

In the UK the annual exempt amount for Capital Gains Tax shields a set amount of total net gains from precious metal disposals each tax year, while gains on Royal Mint legal-tender coins are CGT-exempt without limit.

Thermal conductivity describes how well a material transports heat energy through itself and is expressed in watts per metre and kelvin (W/(m·K)).

The tola is a traditional South Asian unit of weight for gold and silver, equal to exactly 11.6638 grams and widespread above all in India, Pakistan and the Gulf markets.

Tombac is a copper-zinc alloy with a copper content of 67–90%, known for its gold-like colour as a decorative material and historic coinage metal.

The standard weight unit used worldwide in precious metals trading: one troy ounce equals exactly 31.1034768 grams of pure precious metal.

The troy weight system is the internationally binding system of measures for precious metals, whose base unit is the troy ounce of exactly 31.1034768 grams.

A tungsten counterfeit is a fake gold or platinum bar or coin in which a tungsten core is coated with a thin layer of precious metal to exploit the nearly identical density of tungsten (19.25 g/cm³) and gold (19.32 g/cm³).

A non-destructive testing method that uses sound waves in the ultrasonic range to determine the density, internal structure and material composition of precious-metal bars and coins.

Umicore is a Belgian technology group and one of the world's leading precious-metal refiners, whose bars and coin blanks are accredited to LBMA Good Delivery.

Unallocated gold describes a claim to gold against a bank or provider, to which no individually assigned, physically segregated bar or coin corresponds.

The United States Mint is the official coinage authority of the United States and has issued legal-tender coinage as well as gold, silver and platinum bullion coins since 1792.

Investment gold is exempt from VAT in the United Kingdom (HMRC), provided it meets certain minimum requirements for fineness and form; the scheme derives from EU Directive 2006/112/EC.

The purchase of silver (bars, coins, industrial silver) is subject to VAT in the United Kingdom - unlike investment gold, which is VAT-exempt.

Valcambi is one of the world's largest and most respected gold refineries, based in Balerna in the Swiss canton of Ticino, known for the highest purity standards and its patented CombiBar system.

Vermeil is gold-plated sterling silver with a minimum gold layer of 2.5 microns, positioned as a distinct jewellery category between solid gold and simple gold plating.

The Vienna Philharmonic is Austria's best-known bullion coin and one of the most-traded precious metal bullion coins worldwide, available in gold, silver and platinum.

Volatility measures the intensity of price fluctuations over a defined period and is regarded as a central measure of the market risk of an asset.

The Vreneli is a Swiss gold coin with a fineness of 900/1000 (21.6 carat), minted between 1897 and 1949 and today traded as a classic bullion coin.

Wristwatches and pocket watches whose case, bracelet or dial is made wholly or partly of gold, silver, platinum or palladium.

Wealth protection refers to strategies and instruments aimed at preserving the real value of assets against inflation, currency devaluation, crises and political risks.

White gold is a gold alloy to which white metals such as palladium, nickel or silver are added to create the characteristic silvery-white colour.

White gold metals are the precious metals that give gold a silvery-white colour when used as alloying partners — above all palladium, platinum and nickel.

In the UK, income from savings and investments may be taxable, but physical precious metals are not taxed as investment income – on disposal they fall under Capital Gains Tax instead.

A non-destructive analytical method that uses X-rays to precisely determine the elemental composition of precious metals and alloys.

Xetra-Gold is an exchange-traded debt security (ETC) issued by Deutsche Börse Commodities GmbH, physically backed by gold and granting investors a securitised claim to delivery of real gold.

Yellow gold is the classic gold alloy of gold, silver and copper, whose warm yellowish tone comes closest to the pure metal.