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How We Verify Authentic Precious Metals

Counterfeits are getting smarter every year. Here is the layered, multi-point process we use to protect every dollar that passes through our shop — and what you can do at home.

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  • Principle
  • Tools
  • More Methods
  • Destructive vs Non
  • Melt & Assay
  • Slabs
  • Why It Matters
  • Resources

Multi-Point Verification

There is no single test that proves a precious metal is real. Modern counterfeits are built specifically to defeat one or two checks at a time — so we use a layered approach.

Step 1

Multiple Tests

No single tool catches every counterfeit. We run several independent checks on each piece.

Step 2

Layered Coverage

Surface tests, density tests, electronic tests — each covers a different fakery technique.

Step 3

Confirmed Authenticity

When every layer agrees, you and we both walk away confident in the result.

Primary Testing Tools

Six tools we rely on most often, in roughly the order we apply them — from cheapest and fastest to most precise.

Scale

Measures weight to compare against the known weight of an authentic piece. Hobby scales work for casual checks; legal-for-trade scales are required for any commercial transaction.

Price Range
$15 (hobby) — $300+ (legal-for-trade, NTEP-certified)
Ease of Use
Very easy. Place item, read weight.
Strengths
Cheap, fast, and a strong first filter — most counterfeits get the weight wrong because tungsten and lead don't hit gold's exact density.
Limitations
Weight alone never proves authenticity. A clever counterfeiter can match weight if dimensions are also tuned, so always pair with at least one density-aware test.
Acid Testing + Glass Plate

Streak the metal on a glass plate or touchstone, then apply karat-specific acid. The reaction (or lack of it) confirms the karat range.

Price Range
$15 — $40 for a full karat acid kit
Ease of Use
Moderate. Requires care, ventilation, and gloves.
Strengths
Inexpensive, decisive for surface metal, and the established gold standard for jewelers for over a century.
Limitations
Destructive at the test site (small streak). Only tests the outer layer — a thick gold-plated tungsten core can pass acid testing on the surface and fail every other check.
Coin Ping Tester + Mobile App

Tap a coin and capture the resonant ring. An app like the Coin Ping Tester analyzes the frequency signature against a database of known authentic strikes.

Price Range
Free — $20 (app + balance stand)
Ease of Use
Easy. Tap, listen, read the result.
Strengths
Non-destructive, surprisingly accurate for bullion coins, and works on items still in capsules.
Limitations
Coin must be unmounted and freely vibrating. Worn or damaged coins produce noisy readings, and database coverage is limited to popular bullion strikes.
KEE & AuRACLE Testers

Handheld electronic testers that read electrical conductivity through a probe. The KEE family is purity-focused; AuRACLE adds karat readouts and works on most chains and jewelry.

Price Range
$300 — $1,500 depending on model
Ease of Use
Easy. Touch probe to clean metal, read the screen.
Strengths
Non-destructive, fast, and far more decisive than acid for distinguishing 14K from 18K and similar karat lines.
Limitations
Surface-only — defeated by thick plating. Requires a clean spot to make solid probe contact, and readings drift if the probe tip is worn.
Sigma Metalytics Verifier

Reads electromagnetic resistivity through the entire piece. Sigma offers wand-style and platform-style verifiers across multiple price tiers; some require setting the correct dimensions for the item being tested.

Price Range
$700 — $3,000+ (Pro models)
Ease of Use
Moderate. Must select the right wand or dimension setting per item.
Strengths
Reads through plastic, capsules, and slabs. Penetrates the full piece, so it catches plated tungsten and lead-core fakes that surface tests miss.
Limitations
Item dimensions matter — a coin tested with the wrong setting can give a misleading reading. Not a substitute for XRF when surface composition really matters.
XRF Analyzer

X-ray fluorescence reads the actual elemental composition of a metal's surface. Industry standard for refining and high-value verification.

Price Range
$15,000 — $50,000+
Ease of Use
Easy to operate, but requires training and licensing in many jurisdictions.
Strengths
Reports exact percentages of every metal present. Indispensable for slab verification and for items where surface composition truly matters.
Limitations
Reads only the top ~50 microns of surface. Thick gold plating over a tungsten core can fool XRF. Best paired with Sigma to cover both surface and bulk.

How We Use Professional-Grade Equipment

Some of the equipment listed above — XRF analyzers in particular, and high-end Sigma units — requires local licensing for legal use and represents significant capital investment. That puts these tools out of reach for home use and even for most small-scale dealerships, including ours.

For tests that require this equipment, we rely on trusted local partners — refiners and labs who use these instruments in their day-to-day operations. When a piece warrants XRF or Sigma verification, we route it through them and pass the results back to you.

If you ever want to see XRF or Sigma results for a piece, just ask — we'll arrange the test through our partner network.

High-value piece you want professionally verified?

Call or text — (913) 777-4635

Layered, multi-point verification on every piece that walks in.

Supporting Checks

These are the cheap, fast tests we layer in alongside the primary tools.

Magnetism Test

Gold, silver, and platinum are non-magnetic. A strong rare-earth magnet reveals iron- or steel-cored fakes immediately. Quick and free, but it doesn't catch lead, tungsten, or copper-cored counterfeits — those metals aren't magnetic either.

Calipers & Dimension Checks

Authentic bullion has tight tolerances on diameter and thickness. Compare measured dimensions to mint specs. Inexpensive, non-destructive, and a strong filter when paired with weight — most fakes can't match all three at once.

Specific Gravity (Water Displacement)

Suspend the item in water on a scale and calculate density. Gold's density (19.3 g/cm³) is hard to fake without using tungsten (19.25 g/cm³), which is why tungsten is the counterfeiter's metal of choice. A useful confirmatory test that needs no special equipment beyond a scale and a glass.

Visual Inspection

Hallmarks, mint marks, edge reeding, strike sharpness, and surface luster all carry identifying detail. A loupe and a reference catalog beat almost every other tool for spotting obvious fakes — but trained eyes are required to catch high-quality counterfeits.

Destructive vs Non-Destructive Testing

Most of the time we stay surface-level. Sometimes the only way to know is to break the piece down.

Non-Destructive

Sigma, XRF, electronic conductivity testers, ping testing, weight, calipers, and visual inspection. Nothing about the item changes — it goes back to the customer in the same condition it arrived.

Best for: coins, bullion, jewelry, slabs, and any item the seller intends to keep or resell intact.

Destructive

Drilling, cutting, and melting reach metal that surface tests can't. A drilled core sample combined with acid or XRF on the chip catches plated tungsten, lead-fill, and bonded fakes that pass every non-destructive test.

Best for: scrap-bound jewelry, suspect bullion, and any piece headed to the refiner anyway. Never appropriate for graded coins or pieces with collector value.

Melt & Assay — the Final Word

For mixed scrap or items where surface testing isn't enough, the only path to a definitive number is melting and assaying the metal.

  1. Step 1

    Melt

    The lot is melted into a homogeneous bar. Mixed karats, plated pieces, and cores all blend together — no more hidden surprises.

  2. Step 2

    Assay

    A sample is taken from the bar and analyzed by fire assay, ICP, or XRF. The result is the true gold/silver content across the entire lot.

  3. Step 3

    Settle

    The refiner pays based on assayed content, not stated karat. This is the most accurate possible payout for mixed scrap.

For high-value lots, we partner with established refiners who provide assay reports for every settlement. Customers receive a copy of the lot results and a transparent settlement based on the assay.

Slabbed Coins & the Limits of Non-Invasive Testing

Graded and slabbed coins present a unique problem. The plastic case protects the grade and the coin's collector value — but it also blocks every surface test we have. Acid, conductivity probes, and ping testing all need direct contact, and slabs were designed specifically to prevent that.

Sellers are understandably reluctant to crack a slab. Once that case is opened, the coin loses its certified grade and the work that grade represents. So we test through the plastic — and that means relying on tools designed to read through it.

Sigma Metalytics is the workhorse here. It reads electromagnetic resistivity through plastic, so a slabbed coin can sit on the platform fully sealed and still get a valid reading. XRF can read through thin plastic too, though calibration matters more than usual.

Watch out for fake slabs and QR-code spoofing

Counterfeit slabs imitating PCGS and NGC packaging are an active and growing problem. Some now include scannable QR codes that point to look-alike landing pages. Always verify the cert number directly on the grading service's official website — never trust a QR code in isolation. When in doubt, bring it in for a Sigma reading.

Why Authenticity Matters

Counterfeits today aren't the obvious painted-lead fakes of decades past. Modern fakes are produced with real precision: tungsten cores plated to exact gold thickness, struck from authentic-looking dies, sealed in counterfeit slabs with QR codes pointing to look-alike landing pages.

For buyers, that means a single missed verification can cost thousands of dollars. For sellers — even honest ones — it means a piece passed down from family can turn out to be a fake the family didn't know they had.

Verification isn't paranoia. It's the price of trust in this market.

Resources for Collectors & Stackers

A short list of tools and references we trust.

  • PCGS — Verify Cert Number

    Look up any PCGS-graded coin by its cert number to confirm the slab is real.

  • NGC — Verify Cert Number

    Same thing, for NGC-graded coins. Always verify on the official site, never via a QR code on the slab.

  • American Numismatic Association

    Educational resources, grading guides, and a directory of trusted dealers.

  • Sigma Metalytics — Tester Information

    Manufacturer site for the Sigma family of verifiers. Useful if you're considering one for personal use.

A note on home testing: the tools listed in this guide are excellent first lines of defense, but no single home test is foolproof. For high-value items, a professional verification with Sigma, XRF, and a trained eye is the only reliable path to certainty.

Bring it in. We'll verify it.

Walk in, mail it in, or schedule a private appointment. Every piece gets the full multi-point treatment — and you walk away with a real number, not a guess.

Call or Text — (913) 777-4635Try Our Live Pricing Calculator

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