100g Gold Bars

The Metric Sweet Spot for Gold Bars

The 100g gold bar (3.2151 troy ounces) is one of the most popular gold bar sizes in European and Asian markets, and with good reason. Premiums on 100g bars from major refiners run 2-4% over spot, a sharp drop from the 3-6% range typical of 50g bars and only marginally above kilo bars at 1-2%. For investors who can commit the capital (approximately 10,000-10,500 USD at current prices), the 100g size offers near-optimal premium efficiency without requiring the five-figure outlay of a kilo bar.

Valcambi's 100g bar is described as one of the world's best-selling gold products in this format, reflecting the dominance of European buying preferences for metric weights. The 100g PAMP Suisse Fortuna, 100g Argor-Heraeus, and 100g Royal Mint Britannia bar are among the most widely traded alternatives. All are 999.9 fine and come with sealed assay card packaging.

For investors accustomed to troy ounce denominations, 100g translates to approximately 3.22 troy ounces, making it roughly equivalent to three 1 oz gold bars in metal content but at a lower combined premium cost. The metric format is more natural in continental European, Swiss, and Asian markets, where dealers carry extensive 100g inventories and the size is a standard trading unit.

100g Gold Bar Premium Economics

The premium drop from 50g (3-6% over spot) to 100g (2-4%) is one of the sharpest efficiency gains in the gram bar range. This makes the 100g bar a natural choice for investors stepping up from smaller bars and seeking better value per gram without committing to a kilo purchase.

Within the 100g category, PAMP Suisse Fortuna bars carry the highest premiums (typically 3-4% over spot at this weight), driven by the iconic Lady Fortuna design and VeriScan authentication technology. Valcambi bars are usually the most cost-effective from a major Swiss LBMA refiner, often 0.5-1% cheaper than PAMP at purchase. Argor-Heraeus bars fall between the two. The premium gap between refiners narrows at 100g compared to smaller sizes; at 1g, the PAMP-to-Valcambi gap can be 5-10 percentage points.

Compared to buying the same weight in three 1 oz bars, a single 100g bar saves approximately 1-2 percentage points in total premium. Over a significant accumulation programme, this difference compounds meaningfully. The tradeoff is flexibility: three 1 oz bars can be sold individually, while a 100g bar is a single transaction.

The only commonly available bar sizes that offer lower premiums than 100g are 250g, 500g, and 1 kg. The step to 250g roughly halves the premium gap again, reaching 1.5-3%. Kilo bars approach the institutional floor of 1-2%. For most retail investors, 100g represents the point of diminishing returns on premium optimisation, making it the practical sweet spot for cost-efficient gold bar purchases.

Major 100g Gold Bars

The PAMP Suisse 100g Fortuna carries the Lady Fortuna motif that has been the most recognised design in the minted bar market since 1979. Each bar is sealed in CertiPAMP assay packaging and enrolled in PAMP's VeriScan digital authentication system. The 100g size is often cited as the best value per gram in the Fortuna range, as the brand premium narrows significantly compared to smaller denominations while retaining PAMP's strong resale value.

The Argor-Heraeus 100g bar comes from the Swiss refiner (LBMA-accredited since 1961) that is now a subsidiary of the Heraeus Group. These bars feature the kinebar holographic security element on the reverse, a visible holographic pattern that is difficult to replicate and provides immediate visual authentication. The Mendrisio-based refinery has been producing bars since 1951.

The Royal Mint 100g Britannia bar brings government-backed production to the 100g format. As a product of the Royal Mint, it carries the Britannia design and has the assurance of a sovereign mint's quality control. The generic 100g gold bar category, representing products from various LBMA refiners sold without specific brand preference, accounts for a substantial portion of the 100g market and typically offers the lowest premiums available at this weight.

Heraeus and Umicore are prominent European alternatives. Heraeus, a German refiner with LBMA accreditation, is particularly popular in Germany, Austria, and Switzerland. Umicore, headquartered in Belgium, has a strong presence in Benelux and broader EU markets. Perth Mint 100g bars bring government backing from the Western Australian government and are particularly competitive in Asian and Australian markets.

Resale and Storage at 100g

The 100g format has excellent liquidity for LBMA-accredited bars. The size is a standard trading unit in European bullion markets, and bars from PAMP, Valcambi, Argor-Heraeus, Heraeus, Perth Mint, and the Royal Canadian Mint are accepted by dealers worldwide without additional assay requirements, provided the original sealed packaging is intact.

PAMP bars generally retain a higher proportion of their acquisition premium at resale than Valcambi or generic bars, a pattern that holds across all bar sizes but is most pronounced at smaller weights. At 100g, the resale premium gap between refiners narrows. Both PAMP and Valcambi 100g bars trade with tight bid-ask spreads at established dealers.

Authentication is more important at 100g and above than at smaller sizes. The tungsten-core counterfeiting risk, where a gold-plated tungsten bar passes weight and dimension checks because tungsten's density (19.25 g/cm3) is close to gold's (19.32 g/cm3), is primarily a concern for bars of 100g and larger. Standard XRF testing only penetrates 10-50 microns of surface and cannot detect a tungsten core with a thick enough gold shell. Ultrasonic testing, which exploits the different sound velocities of gold (3,240 m/s) and tungsten (5,170 m/s), is the most reliable non-destructive verification method. Buying from authorised dealers in sealed assay cards eliminates this risk for retail buyers.

Physically, a 100g gold bar is compact, roughly 47mm by 27mm by 5mm depending on the manufacturer. It fits in a shirt pocket and stores extremely efficiently. Assay cards are flat and stack well in a safe or vault drawer. The entire value of a 100g bar (approximately 10,000-10,500 USD) occupies less space than a matchbox.