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How We Test & Verify Your Precious Metals

Professional-grade equipment. Transparent process. Every test done right in front of you.

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At Georgia Gold Buyers, we don't guess — we use the same testing technology trusted by refineries, assay offices, and the U.S. Mint. When you bring your items to us, every test is performed right in front of you, so you can see exactly how we determine what your gold, silver, or platinum is worth.

Our testing process combines multiple methods to ensure the highest possible accuracy. No single test tells the whole story — that's why we cross-verify using different technologies.

XRF Analyzer (X-Ray Fluorescence)

Our XRF (X-Ray Fluorescence) analyzer is the gold standard in precious metals testing — the same technology used by refineries, assay offices, and major jewelry houses worldwide.

How it works: The XRF emits a precisely calibrated beam of X-rays that excites the atoms in your metal. Each element responds with its own unique energy signature — like a fingerprint. The analyzer reads these signatures and provides an exact breakdown of every element present in your item within seconds.

Why this matters to you: Unlike acid tests that only estimate a karat range, the XRF gives us the precise purity percentage. This means you get paid for exactly what your gold is — not a rough estimate. It's also completely non-destructive. Your items are never scratched, cut, or chemically altered.

What we test with XRF: All gold jewelry, coins, bullion, silver items, platinum pieces, and any item where exact purity matters.

What It Tells Us

  • Exact gold content to within 0.01% (e.g., 58.37% gold = 14K)
  • Complete elemental composition — gold, silver, copper, platinum, palladium, zinc, nickel, and more
  • Detection of gold plating vs. solid gold
  • Identification of unknown or unmarked items

Sigma Metalytics Precious Metal Verifier

The Sigma Metalytics Precious Metal Verifier uses patented electromagnetic technology to verify the authenticity of precious metal coins and bullion — from the inside out.

How it works: The Sigma sends electromagnetic waves deep into the metal sample. These waves measure the bulk resistivity of the metal — a physical property that's virtually impossible to fake. The device compares the reading against a database of known authentic metals. If the reading falls within the expected range, the item is verified. If it falls outside, something is wrong.

Why this matters to you: Counterfeit gold and silver bullion is a growing problem. Gold-plated tungsten bars, fake silver eagles, and counterfeit coins are more sophisticated than ever. The Sigma Verifier catches fakes that other methods miss, because it reads the actual metal composition below the surface — not just what's on top.

What we test with Sigma: Gold and silver coins, bullion bars, rounds, and any item where authenticity verification is critical. Especially important for high-value purchases like American Gold Eagles, Krugerrands, and silver bars.

What Makes It Special

  • Penetrates below surface plating — reads the core metal, not just the surface
  • Tests through protective holders and capsules — no need to remove coins from packaging
  • Non-destructive — no chemicals, no scratching, no damage whatsoever
  • Identifies counterfeits that pass visual inspection and even acid tests

Touchstone & Acid Testing

The touchstone and acid test is one of the oldest and most reliable methods for determining gold karat — used by goldsmiths for over 2,500 years.

How it works: We firmly streak your gold item across a specially treated black touchstone, leaving a thin deposit of metal on the stone's surface. We then apply calibrated acid solutions (10K, 14K, 18K, 22K) to the streak. The acid's reaction — whether the streak dissolves, fades, or remains intact — tells us the karat of your gold. We compare the reaction against known gold reference needles of certified karats.

Why this matters to you: The acid test is a tried-and-true confirmation method. While our XRF gives exact digital readings, the acid test provides visible, tangible proof. You can watch the reaction happen in real time and see for yourself. It's also the only test that reliably detects gold-filled items (which have a thick layer of gold bonded to a base metal).

What we test with acid: Gold jewelry where we want a second verification, items with unusual readings on the XRF, and gold-filled or gold-plated items where we need to determine whether the item is solid gold.

What It Tells Us

  • The karat range of your gold (10K, 12K, 14K, 18K, 22K, 24K)
  • Whether an item is gold-plated vs. solid gold (acid eats through plating quickly)
  • Confirmation of XRF results through an independent method

Lab-Grade Precision Scales

Weight is half the value equation. Even a small error in weight measurement can mean a significant difference in your payout. That's why we use lab-grade precision scales — not consumer-grade jewelry scales.

How it works: Our scales measure to 0.01 grams (that's one-hundredth of a gram) and are regularly calibrated using certified reference weights. Every item is weighed individually on a clean, stable surface. We record the weight and show it to you on the display.

Why this matters to you: A 14K gold chain that weighs 15.00 grams vs. one that weighs 15.45 grams represents a real difference in value — potentially $20–30 or more at today's gold prices. Cheap scales round and fluctuate. Lab-grade scales give you the true weight, and the true weight means a fair payout.

What we weigh: Everything. Every item is individually weighed after testing. We never estimate weight by feel or appearance.

Precision Matters

  • Measures to 0.01 grams — one-hundredth of a gram
  • Regularly calibrated with certified reference weights
  • Every item weighed individually — never estimated
  • Weight shown to you on the display in real time

Fire Assay (Melt & Assay Capability)

For the highest level of accuracy — the same method used by refineries and the U.S. Mint — we have the capability to perform fire assay testing. This is the definitive test for precious metals purity.

How it works: The metal is melted in a crucible at extremely high temperatures (over 1,000°C). During the melting process, base metals and impurities are separated from the precious metal. The resulting pure metal is then analyzed with our XRF to determine exact precious metal content. This produces a formal assay report — the same documentation refineries provide.

When we use it: Fire assay is reserved for special cases:

  • Large lots of scrap gold where exact purity is critical for pricing
  • Disputed items where standard testing results are inconclusive
  • Customers who want a formal assay report for their records
  • Large estate collections where the volume justifies the process

Why this matters to you: Having fire assay capability means we can resolve any question about purity with absolute certainty. Most gold buyers send items to a refinery for assay and make you wait days or weeks for results. We do it in-house.

The Definitive Test

  • Same method used by the U.S. Mint and major refineries worldwide
  • Produces a formal assay report for your records
  • Done in-house — no waiting days or weeks for results
  • Resolves any purity question with absolute certainty

Density Test (Water Displacement)

The density test is one of the most reliable ways to verify precious metals, because every metal has a unique density that's extremely difficult to fake. Gold is dense — far denser than almost any base metal a counterfeiter might substitute. By measuring an item's density, we can determine whether the metal is genuine and even identify its approximate karat.

How it works: We first weigh the item on our precision scale in air. Then we suspend the item in a water-filled tub on the scale and weigh it again while submerged. The difference between the dry weight and the submerged weight tells us the volume of water the item displaces. From there, we calculate density using a simple formula:

Density = Dry Weight ÷ (Dry Weight − Submerged Weight)

The result is measured in grams per cubic centimeter (g/cm³). We then compare the measured density against the known density of each metal and karat to determine what the item is.

Why this matters to you: A gold-plated tungsten bar can fool an acid test and even some electronic testers — but it can't fool the density test. Tungsten is one of the only metals close to gold's density (19.3 g/cm³ vs. 19.32 g/cm³), which is why counterfeiters use it. But for most alloys and karats, the density test is definitive. A lead-core fake, a brass fake, or a copper fake will have completely different density from real gold.

What we test with density: Coins, bullion bars, ingots, and any item where weight feels suspicious relative to size. It's also a quick verification for large items that are difficult to test with the XRF sensor window.

Gold Density by Karat

Each gold karat has a unique density because of the different ratios of gold to alloy metals (typically copper and silver). This is what makes the density test karat-specific.

Karat Purity Density (g/cm³) Notes
24K99.9%19.32Pure gold — the densest
22K91.7%17.7 – 18.0Common in coins (Eagles, Krugerrands)
18K75.0%15.2 – 15.9Fine jewelry standard
14K58.3%12.9 – 14.6Most common U.S. jewelry
10K41.7%11.3 – 13.1Minimum legal U.S. gold
9K37.5%10.9 – 12.7Common in UK/Australian jewelry

Density ranges vary based on alloy composition (yellow gold vs. white gold vs. rose gold use different alloy metals). Our team accounts for these variations when interpreting results.

Other Precious Metal Densities

Metal Density (g/cm³) Comparison
Pure Gold (24K)19.32The benchmark
Platinum (950)21.45Denser than gold
Palladium12.02About 62% of gold's density
Fine Silver (999)10.49About 54% of gold's density
Sterling Silver (925)10.36Slightly less than fine silver
Tungsten19.25Nearly identical to gold — used in counterfeits
Lead11.34Much less than gold — easy to detect
Copper8.96Less than half of gold's density
Brass8.4 – 8.7Common fake gold material — easy to catch

Why Density Works

  • Every metal has a unique, measurable density
  • Can determine karat from density alone
  • Catches lead-core, brass, and copper fakes instantly
  • Non-destructive — just water, no chemicals
  • Based on Archimedes' principle — proven physics
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Sound Test (Ping Test) for Coins

Experienced precious metals dealers have used the "ping test" for generations. When a genuine gold or silver coin is struck or tapped, it produces a distinctive, clear, high-pitched ring that sustains for several seconds. Fake coins sound flat, dull, or muted — the difference is immediately obvious once you know what to listen for.

How it works: We balance the coin on a fingertip and gently tap it with another coin or a small metal rod. A genuine precious metal coin will produce a bright, sustained ring — like a tiny bell. The pitch, duration, and clarity of the sound are all indicators of the coin's composition.

Why it works: Sound travels through metal at different speeds depending on the metal's density, elasticity, and molecular structure. Precious metals like gold and silver have unique acoustic properties:

  • Gold coins produce a soft, warm, sustained ring with a lower pitch
  • Silver coins produce a bright, clear, high-pitched ring that sustains for 3–5 seconds — often described as "bell-like"
  • Fake coins (base metal, tungsten-core, or plated) produce a dull thud, a flat clank, or a ring that dies immediately

Why this matters to you: The ping test is fast, free, and requires no equipment. It's especially useful as a first-pass check on coins and rounds. If a coin doesn't ring right, we immediately know to investigate further with the Sigma Verifier, density test, or XRF. Many counterfeits that look perfect visually fail the ping test instantly.

What we test with the ping: Gold and silver coins (American Eagles, Maple Leafs, Krugerrands, Morgan dollars, Peace dollars), silver rounds, and bullion coins of all types. The ping test is specifically for coins and rounds — it doesn't work on bars, jewelry, or irregularly shaped items.

Listen for Authenticity

  • Genuine silver coins ring like a bell for 3–5 seconds
  • Fake coins produce a dull thud or flat clank
  • Instant, no-equipment screening for coins and rounds
  • Used by dealers for generations — proven reliability
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Magnet Test

The magnet test is the simplest and fastest screening test in our toolkit. It takes two seconds and immediately tells us whether an item could be fake. While it can't confirm an item is genuine, it can instantly rule out many common counterfeits.

How it works: We use a strong rare-earth neodymium magnet and bring it close to the item. Genuine precious metals are not magnetic:

  • Gold — not magnetic (diamagnetic). A real gold item will not be attracted to a magnet at all.
  • Silver — not magnetic, but exhibits a unique property: if you slide a strong magnet slowly down a silver bar or coin, the magnet will visibly slow down (called the Lenz effect). This braking effect is a strong indicator of genuine silver.
  • Platinum — very slightly paramagnetic (may show a faint attraction), but nothing like steel or iron.
  • Palladium — not magnetic.

What a magnet reaction tells us:

  • Strong attraction — The item contains iron, steel, or nickel. It is NOT genuine precious metal (or has a ferrous core). Immediate red flag.
  • No attraction — Consistent with genuine gold, silver, or platinum. But not proof by itself — some non-precious metals (copper, brass, aluminum, lead, tungsten) are also non-magnetic. That's why we always follow up with additional tests.
  • Lenz effect on silver — A strong magnet slides slowly and visibly brakes when dragged along genuine silver. This doesn't happen with silver-plated base metals.

Why this matters to you: The magnet test is our first line of defense. If an item sticks to a magnet, we know instantly that it's not what it claims to be — and we can save you time by flagging it immediately. For items that pass the magnet test, we proceed to more precise methods (XRF, Sigma, density) to verify exact composition.

What we test with magnets: Everything gets a quick magnet check as a first screening step — jewelry, coins, bullion, bars. It takes two seconds and can immediately flag items that would otherwise waste time on more detailed testing.

Quick Facts

  • Gold, silver, and palladium are NOT magnetic
  • If it sticks to a magnet, it's not real precious metal
  • Silver shows a unique "braking" effect with magnets
  • 2-second screening that catches many fakes instantly
  • Always followed by more precise testing methods

Why Our Testing Process Matters

Four pillars that protect your interests and ensure a fair payout.

Transparency

Every test is done in front of you. You see the XRF reading, watch the acid reaction, and read the scale yourself. Nothing happens behind a curtain.

Accuracy

We use multiple testing methods and cross-verify results. Our XRF is accurate to 0.01%. Our scales measure to 0.01 grams. You get paid for exactly what you have.

No Damage

Our primary testing methods (XRF and Sigma) are completely non-destructive. Your items are returned to you in the same condition if you choose not to sell.

Your Protection

Counterfeit precious metals are a real and growing problem. Our multi-method approach protects both you and us. If something isn't genuine, we'll tell you — and explain why.

Bring Your Items In

Not sure what your items are worth? Not sure if they're even real gold? Bring them in. Our testing is always free, always transparent, and always comes with zero obligation to sell.

Testing FAQs

Common questions about our testing process.

No. Our primary testing methods — XRF analysis and Sigma Metalytics verification — are completely non-destructive. Your items are never scratched, cut, or chemically altered. The only method that leaves any mark is the touchstone acid test, which requires a tiny streak on a stone — not on your item itself. If you choose not to sell, you leave with your items in the same condition you brought them.
Individual items take 30–60 seconds each. A handful of jewelry items might take 5–10 minutes total. Larger collections with dozens of pieces can take 30–60 minutes. We never rush the process — accuracy is more important than speed.
Yes. We regularly test coins, bars, and jewelry that customers purchased online or from other sources. If you want to verify authenticity before adding to your collection, bring it in. We'll test it for free whether or not you're looking to sell.
Many older pieces, handmade jewelry, and international items have no stamp at all. That doesn't mean they aren't gold. Our XRF analyzer doesn't need a stamp — it reads the actual metal composition. We frequently test unmarked items and discover they're solid gold.
Coins and bullion are tested primarily with the Sigma Metalytics Verifier, which is specifically designed for this purpose. It can test through protective holders without removing the coin. Jewelry is typically tested with the XRF for exact karat determination, then weighed on our precision scales. We may also use the acid/touchstone test as a secondary confirmation.
"I had the best experience selling my old jewelry. The process was super smooth and I felt really comfortable the whole time. Gadson and Glenn were so honest and gave me a fantastic price."
— Samantha Y. ★★★★★
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