Assay Card Bar (Blister)
Also: Blister Bar, Assay Card, Certificate Bar
A precious metal bar sealed into a tamper-evident plastic blister pack bearing a printed certificate of authenticity issued by the refinery.
An assay card bar in a blister combines the physical precious metal bar with a directly printed or enclosed certificate of authenticity, permanently fixed in a sealed transparent plastic packaging (blister). The seal is constructed so that opening it becomes irreversibly visible – a broken blister is considered a breach of trust and significantly reduces the dealer resale value. Buyers thus receive at a glance a guarantee of fineness, weight, serial number, and refinery, without needing to handle the piece itself.
Structure and Features
A typical blister bar consists of three layers:
- Bar – usually a minted fine gold bar (999.9 ‰) or fine silver bar (999 ‰) in small to medium denominations.
- Carrier/certificate card – sturdy cardboard or aluminium bearing details of weight, fineness, serial number, and the logo of the refinery.
- Blister film – transparent, heat-sealed or ultrasonic-welded plastic layer that fixes the bar to the card.
Leading refineries such as PAMP Suisse, Valcambi, Heraeus, or Argor-Heraeus additionally stamp a hologram or QR code on the card for digital verification.
Typical Denominations
| Weight | Metal | Fineness |
|---|---|---|
| 1 g | Gold | 999.9 ‰ |
| 5 g | Gold | 999.9 ‰ |
| 10 g | Gold | 999.9 ‰ |
| 1 g | Silver | 999 ‰ |
| 10 g | Platinum | 999.5 ‰ |
Small denominations are well suited to gifts, savings plans, and beginners – the Gold Calculator shows the current metal value per gram.
Premium and Liquidity
Assay card bars carry a higher premium (agio) than comparable loose bars due to packaging, certification, and handling costs. For resale: blister intact = full dealer buying price; opened blister = melt value basis minus deduction. The current melt value is determined by the Melt Value Calculator. For denominations up to 100 g the premium is typically significantly higher than for kilo bars – this is the price for forgery protection and easy storage.
Forgery Protection and Testing
The sealed unit considerably impedes manipulations such as drilling out or replacing the core with tungsten. Nevertheless, experts recommend additional methods in cases of doubt: weight verification, Archimedes density measurement, or X-ray fluorescence analysis (XRF). The Authenticity Checker provides reference values for weight and dimensions.
Note: Tax treatment (VAT, speculative holding period) depends on the metal, holding period, and individual circumstances – this does not constitute tax or investment advice.
In Brief
Assay card bars in blisters combine physical security with documented authenticity and are particularly suitable for small weight classes and safe transfer – as long as the seal remains intact, the resale value is straightforwardly verifiable.