A 1oz gold bar from PAMP and a 100g gold bar from PAMP can look completely different — one is shiny, struck like a coin, sealed in a credit-card sized assay holder; the other is dull, rough-edged, with a separate paper certificate. Same metal, same purity, different production methods.

Minted bars

Made by stamping a polished blank between two engraved dies under high pressure — essentially the same process as striking a coin.

Characteristics:

  • Mirror or matte finish, depending on design.
  • Crisp edges, lettering and ornament.
  • Almost always sold sealed in a tamper-evident assay card.
  • Range: typically 1g to 100g for gold; 1g to 1oz for silver.

Costs more per gram because:

  1. The blank has to be polished.
  2. Each strike consumes die life — dies wear and have to be replaced.
  3. The card-sealing process adds packaging cost.
  4. The presentation finish carries a marketing premium.

Cast bars

Made by pouring molten metal into a mould and letting it cool, then assigning a serial number and an accompanying certificate.

Characteristics:

  • Dull, slightly grainy surface — often with visible flow lines.
  • Rounded edges and irregular thickness.
  • Sold loose with a separate paper assay certificate.
  • Range: typically 100g to 1kg for gold; 100g to 5kg for silver.

Cheaper per gram because:

  1. No die wear — just a mould that lasts for thousands of bars.
  2. No polishing, no marketing finish.
  3. Bare-bones packaging.

Typical UK premium comparison

FormatSizeTypical UK premium over spot
Gold minted bar1oz3.5–6%
Gold minted bar50g4–5%
Gold cast bar100g2–3%
Gold cast bar1kg1.5–2.5%
Silver minted bar1oz25–35%
Silver cast bar1kg11–14%

The pattern is consistent: cast bars are cheaper per gram of metal, especially at 100g+ sizes. Minted bars cost more in absolute terms but their unit-price-per-gram becomes comparable at 1oz and below.

Which to buy

Minted bar — good for:

  • Gifting — the presentation finish and sealed card look like jewellery.
  • Small sizes (1g–10g) where you’d want the assay card for authenticity verification.
  • Resale through online dealers that prefer intact PAMP Veriscan or Royal Mint DNA Certified cards.

Cast bar — good for:

  • Maximum metal per pound spent at 100g+ sizes.
  • Stackers who don’t care about presentation.
  • Institutional storage where bars enter vault and are weighed/tested individually anyway.

Authenticity in cast bars

A common worry: “the bar isn’t sealed in a card, how do I verify it?”

Reputable cast bars carry:

  • Stamped serial number on the bar itself.
  • Refiner mark (PAMP, Metalor, Umicore, Royal Mint, Heraeus, Argor-Heraeus).
  • Stated weight and fineness stamped.
  • Paper assay certificate with matching serial.

If you buy a 1kg cast bar from a major UK dealer, they will have verified it against a Sigma analyser or XRF on receipt from the refiner. The assay certificate is a chain of custody, not the only line of defence.

How to spot fake bullion →

CombiBars — the third format

Valcambi Suisse CombiBars are a hybrid: a single bar with perforated 1g segments that snap apart. Premium is high (around 8–10% for a 50×1g gold CombiBar) but you get the divisibility of 50 individual 1g bars in one package — useful for incremental selling or a doomsday-scenario “barter” stash.

Quick decision tree

  1. Buying ≥ 100g of gold? → Cast bar (lowest premium per gram).
  2. Buying ≤ 1oz of gold? → Minted bar (assay card matters more at small sizes).
  3. Buying silver in any quantity? → Either — but cast 1kg silver is the cheapest format per gram.
  4. Buying for a gift / occasion? → Minted bar (better presentation).

Browse all bars →