7 Gold Bar Sizes and Weights Explained
Investors can buy gold bars in sizes ranging from tiny 1-gram wafers to hefty 400 troy ounce bricks. Each size has its own characteristics in terms of weight, dimensions, form, purity, brand options, premiums, and resale factors. Below we break down seven of the most common gold bar sizes – 1 g, 10
Key takeaways
- Weight: 1 gram (~0.0322 ozt of gold).
- Dimensions: ~8 mm x 15 mm x 0.4 mm (about the size of a fingernail)[1].
- Form: Minted bar (cut and stamped for a refined look). Comes in tamper-evident assay packaging.
- Purity: Usually .999 or .9999 fine gold (24k). Virtually all 1g bars from major refiners are 99.9%+ pure.
- Common Brands: PAMP Suisse (Lady Fortuna 1g bars), Valcambi (often sold in CombiBar sheets), Perth Mint, Argor-Heraeus, and other LBMA-approved refiners.
Comparison of common gold bar sizes from 1 gram up to 1 kilogram. A 400 oz “Good Delivery” bar (not shown) is much larger.
Investors can buy gold bars in sizes ranging from tiny 1-gram wafers to hefty 400 troy ounce bricks. Each size has its own characteristics in terms of weight, dimensions, form, purity, brand options, premiums, and resale factors. Below we break down seven of the most common gold bar sizes – 1 g, 10 g, 1 oz, 50 g, 100 g, 1 kg, and 400 ozt – with key facts and considerations for each. Whether you’re looking for the “small bills” of the gold world or institutional Good Delivery bars, this guide will help you understand the differences[1][2].
1) 1 Gram Gold Bar (0.032 Troy oz)
At just 1 gram of gold, this is one of the smallest investment-grade bars. It contains 0.03215 troy ounces of pure gold. These tiny bars are highly portable and often come sealed in assay cards the size of a credit card for protection and authenticity. They are typically minted bars with polished finishes and detailed inscriptions.
Weight: 1 gram (~0.0322 ozt of gold).
Dimensions: ~8 mm x 15 mm x 0.4 mm (about the size of a fingernail)[1].
Form: Minted bar (cut and stamped for a refined look). Comes in tamper-evident assay packaging.
Purity: Usually .999 or .9999 fine gold (24k). Virtually all 1g bars from major refiners are 99.9%+ pure.
Common Brands: PAMP Suisse (Lady Fortuna 1g bars), Valcambi (often sold in CombiBar sheets), Perth Mint, Argor-Heraeus, and other LBMA-approved refiners.
Typical Premium: Very high – around 40% over spot price on average[3]. Production costs are the same as for larger bars, so the premium per gram is steep for these “micro” bars.
Resale Considerations: 1g bars are easy to liquidate in small amounts (they’re the “small bills” of gold)[1], but expect a wider buy-sell spread. Dealers may pay close to melt value, so the initial high premium is hard to fully recover. They are IRA-eligible if produced by an approved refiner (.995+ fineness)[8]. Keep them in their sealed assay cards for maximum resale value and authenticity assurance.
Quotable Fact: “These [1g bars] are like the ‘small bills’ of the gold world.”[1]
2) 10 Gram Gold Bar (0.32 Troy oz)
The 10 gram gold bar offers about a third of an ounce of gold, bridging the gap between tiny gram bars and a full ounce. It’s often cited as the smallest bar that feels substantial in hand, with a bit of heft despite its compact size[1]. Like the 1g, it’s typically a minted bar with high purity.
Weight: 10 grams (~0.3215 ozt).
Dimensions: ~18 mm x 31 mm x 1 mm (approximately the size of a postage stamp)[1].
Form: Minted bar. Sharp edges and polished surfaces, usually delivered in an assay card.
Purity: .999 or .9999 fine gold.
Common Brands: PAMP, Credit Suisse, Valcambi, Perth Mint, Royal Canadian Mint (though RCM’s smallest gold bar is often 1 oz).
Typical Premium: Moderate – around 6–8% over spot on average[3].
Resale Considerations: Fairly liquid globally and IRA-eligible (.995+ pure)[8]. Keep sealed packaging intact for best buyback prices.
Quotable Fact: “The conveniently-sized 10 gram bar is the smallest bar that still feels weighty and solid when you hold it.”[1]
3) 1 Troy Ounce Gold Bar (31.1 grams)
One troy ounce (31.1035 g) is the most popular gold bar size in the world[1]. Even in metric jurisdictions, 1 ozt bars are common because the troy ounce is the international standard for precious metals.
Weight: 1 troy ounce (31.1 grams exactly).
Dimensions: ~24 mm x 42 mm x 2 mm – about the footprint of a military dog tag, but a bit thicker[1].
Form: Typically minted (cast exists but is less common).
Purity: .999 or .9999 fine[2].
Common Brands: PAMP Suisse, Valcambi, Perth Mint, Royal Canadian Mint, Argor-Heraeus, Johnson Matthey/Engelhard (vintage), Sunshine Mint, etc.
Typical Premium: Low – around 3–5% over spot on average[3].
Resale Considerations: Excellent liquidity; tight spreads; IRA-approved when from accredited refiners[8].
Quotable Fact: “The 1 Troy oz gold bar is the most common size traded around the world.”[1]
4) 50 Gram Gold Bar (1.61 Troy oz)
At 50 grams, this bar contains just over 1.5 troy ounces of gold. It feels very solid in the palm – a step up in heft from a 1 oz bar[1].
Weight: 50 grams (~1.607 ozt).
Dimensions: ~25 mm x 45 mm x 2.3 mm (roughly 1 x 1.8 inches)[1][3].
Form: Mostly minted; notable Valcambi 50g CombiBar™ can break into fifty 1g mini-bars[9].
Purity: .999 or .9999 fine.
Common Brands: Valcambi, PAMP, Perth Mint, Argor-Heraeus, Emirates Gold.
Typical Premium: Low – around 3–4% over spot[3].
Resale Considerations: Good balance between size and liquidity; IRA-eligible (.995+)[8]. Keep CombiBars intact if selling as a 50g unit.
Quotable Fact: “A 50 gram gold bar… can be more economical than buying fifty 1-gram bars or five 10-gram bars.”[1]
5) 100 Gram Gold Bar (3.22 Troy oz)
A popular mid-sized bar chosen for low premiums and manageable size[3].
Weight: 100 grams (~3.215 troy oz).
Dimensions: ~31 mm x 55 mm x 3 mm[1].
Form: Minted or cast (both common)[6].
Purity: .999 or .9999 fine.
Common Brands: PAMP, Valcambi, Argor-Heraeus, Credit Suisse, Perth Mint, Royal Mint, RCM, etc.
Typical Premium: Very low – about 2.5–3% over spot[3].
Resale Considerations: Widely recognized by dealers; limits flexibility if you need to sell in smaller portions later[1]; IRA-eligible[8].
Quotable Fact: “Though the price-per-gram is low, a [100g] bar this size limits your options if you ever want to liquidate little-by-little.”[1]
6) 1 Kilogram Gold Bar (32.15 Troy oz)
A benchmark size for serious investors; roughly the size of a smartphone but extremely dense[1].
Weight: 1,000 g = 1 kg = ~32.15 ozt.
Dimensions: ~40 mm x 80 mm x 18 mm (approx.)[1][4].
Form: Typically cast.
Purity: .999 or .9999 fine; at minimum .995 (LBMA standard)[2].
Common Brands: PAMP, Valcambi, Perth Mint, RCM, Heraeus, Metalor, Argor-Heraeus, etc.
Typical Premium: Very low – ~2–3% (often less)[3].
Resale Considerations: Highly liquid with major dealers; tight spreads; storage/security important; IRA-eligible[8].
Quotable Fact: “Though it’s essentially the same size as an iPhone 6, a 1 kilo gold bar weighs substantially more since gold is so dense.”[1]
7) 400 Troy Ounce Gold Bar (Good Delivery Bar)
The iconic wholesale bar traded by central banks and institutions.
Weight: ~400 ozt fine gold (bars range 350–430 ozt gross)[5].
Dimensions: ~250 × 70 × 35 mm (LBMA range allows variation)[4][5].
Form: Cast; stamped with refiner, serial, fineness, year (post‑2019)[4].
Purity: Minimum .995 (often higher)[4][5].
Common Brands: LBMA Good Delivery refiners (e.g., PAMP, Valcambi, Metalor, Perth Mint, RCM, Rand Refinery, Asahi, Heraeus)[4].
Typical Premium: Extremely low – ~0–2% over spot[5][3].
Resale Considerations: Excellent liquidity only in institutional channels; impractical for retail; chain‑of‑custody and vaulting are critical; IRA‑eligible by spec but rarely offered to retail IRAs[3][8].
Quotable Fact: “A 400-oz gold bar will probably be very close to the spot price, but you will probably not be able to resell it unless you are an institution.”[3]
Comparison Table of Gold Bar Sizes
Bar Size | Weight (grams) | Weight (troy oz) | Typical Dimensions | Common Form | Purity | Typical Premium | Notes |
|---|---|---|---|---|---|---|---|
1 gram | 1 g | 0.032 ozt | ~8×15×0.4 mm[1] | Minted | .999–.9999 | ~40%[3] | Ultra-small; high premium, easy to gift. |
10 gram | 10 g | 0.32 ozt | ~18×31×1 mm[1] | Minted | .999–.9999 | ~7%[3] | Small bar, moderate premium, popular globally. |
1 troy oz | 31.1 g | 1.00 ozt | ~24×42×2 mm[1] | Minted | .999–.9999 | ~4%[3] | Most common size; very liquid worldwide. |
50 gram | 50 g | 1.61 ozt | ~25×45×2.3 mm[1] | Minted | .999–.9999 | ~3%[3] | Lower premium; sometimes divisible (CombiBar). |
100 gram | 100 g | 3.22 ozt | ~31×55×3 mm[1] | Minted/Cast | .999–.9999 | ~3%[3] | Popular “mid-size”; good value, less flexible than smaller bars. |
1 kilogram | 1000 g | 32.15 ozt | ~40×80×18 mm[1] | Cast | .999–.9999 | ~2–3%[3] | Largest common retail bar; very low premium, heavy to handle. |
400 oz Good Delivery | ~12,400 g | ~400.0 ozt | ~250×70×35 mm[4] | Cast | .995–.9999 | ~1%[5] | Wholesale bar; minimal premium, not practical for individuals. |
Dimensions vary by refiner and form; premiums fluctuate with market conditions. All investment bars are at least .995 fine per market standards[4][5].
Gold Bar Evaluation Rubric
Market Prevalence & Liquidity (35%)
Ease of Resale & Verification (25%)
Premium Efficiency (20%)
Storage & Handling (20%)
(Example: 1 oz bars score high across categories; 400 oz bars score high on premium efficiency but low on retail resale and handling.)
Myth vs. Fact: Gold Bar Purity & Form
Myth: “All gold bars are 99.99% pure, and minted bars are ‘better’ than cast bars.”
Fact: Good Delivery bars can be as low as .995 while many retail bars are .9999. Purity is independent of form—cast and minted bars from reputable refiners are equally pure and valuable by weight[7][6]. Minted bars look nicer and often carry higher premiums, but a cast 100g .9999 bar contains the same gold as a minted one and sells for melt just the same.
FAQs
Q1: What is the most popular gold bar size for investment?
A: The 1 troy ounce bar—widely recognized, easy to store, and low premium[1][3].
Q2: Why do smaller gold bars (like 1g or 5g) have higher premiums?
A: Fixed production/packaging costs spread over very little gold raise the % premium[1][3].
Q3: Are gold bars eligible for IRAs?
A: Yes, if .995+ pure and from approved refiners; stored with an approved custodian[8].
Q4: How can I be sure a gold bar is authentic?
A: Buy from reputable dealers; look for assay/serials; verify weight/dimensions; dealers may XRF/ultrasonic test[1][5][9].
Q5: How do I sell a large bar like 1 kg or 400 oz?
A: Work with major bullion dealers/banks; 400 oz bars trade in institutional vault systems[5][3].
Q6: Does form (cast vs minted) change resale value?
A: Gold content drives value; minted may carry slightly higher premiums if pristine in assay, but both sell for melt by weight/purity[6][7].
Buying, Selling, and Collecting Tips
Buy From Reputable Sources.
Compare Premiums & Shop Around (especially on small bars)[3].
Keep Packaging & Certificates Intact (don’t cut bars out of assay)[9].
Consider Liquidity Needs (smaller bars for flexibility; kilos for low premiums)[3].
Verify With Scale & Calipers on receipt (match specs)[1].
Understand Buyback Policies and round‑trip spreads.
Mini‑Glossary
Troy Ounce (ozt): 31.1035 g; standard for precious metals[3].
Gram: Metric unit; 31.1035 g = 1 ozt[3].
Good Delivery: LBMA standard for ~400 oz bars; strict specs on weight, purity, dimensions, markings[4].
Cast Bar: Poured ingot; rougher finish; lower premiums[6].
Minted Bar: Stamped from rolled strip; polished; higher premiums[6].
Assay Card/Certificate: Refiner’s guarantee of weight/purity/serial; keep intact for resale[9].
Fineness/Purity: Parts per 1000 (.995, .999, .9999). LBMA Good Delivery min .995[4].
Premium/Spread: % above spot to buy / below spot to sell; varies by size/brand[3].
LBMA: London Bullion Market Association; accredits refiners and maintains Good Delivery Lists[4].
Compliance Note: Educational only; not financial or legal advice.
Sources
[1]: U.S. Gold Bureau – Gold Bar Dimensions / Sizes (How Big is a Gold Bar?).
[2]: GoldCore – Gold bar purities and Good Delivery overview.
[3]: Bullion.Directory & Pacific Precious Metals – Premiums vs. size; spread insights.
[4]: LBMA Good Delivery Rules – Specifications and tolerances.
[5]: GoldCore – 400 oz London Good Delivery Bar (specs & pricing).
[6]: JM Bullion – Cast vs. Minted Bars (forms, premiums).
[7]: Universal Coin & Bullion – Minted vs. Cast Bars (purity/value).
[8]: IRS/IRA references – Purity & custodian requirements (iraadvantage.net; mountainwestira.com).
[9]: APMEX – Valcambi 50g CombiBar (breakable bar features).