How to spot a fake NBU coin

1. Compare weight and diameter to the catalog

Every NBU coin has exact specifications: mass (grams), diameter (millimeters) and metal. Fakes almost always miss at least one, because reproducing a precise alloy is hard and expensive.

• Weigh the coin on a jeweler's scale (0.01 g precision) and compare to the catalog mass.
• Measure the diameter with calipers — a deviation over 0.1–0.2 mm is suspicious.
• A weight deviation of more than 2–3% is a reason to look closer.

2. The magnet test

NBU commemorative coins are struck from nickel silver, silver or gold — none of which are magnetic. If a coin is attracted to a magnet even slightly, it's almost certainly a fake made of steel or a ferromagnetic alloy.

3. Edge and relief

An original has crisp, even relief and a clean edge. Fakes often have a blurry design, uneven lettering, and casting marks (tiny bubbles, a seam along the edge).

• Inspect fine details under magnification — on an original they are sharp.
• The edge should be uniform: reeded, lettered or plain — exactly as in the catalog.
• A casting seam along the edge indicates a homemade cast.

4. Sound (the ring)

A silver coin, tapped lightly against another, produces a clear, ringing, long tone. Fakes made of cheap alloys sound dull and short. Not foolproof, but useful as an extra check.

5. Compare with a reference photo

Open the official image of the coin (obverse and reverse) and check every detail: font, placement of text, portrait, small elements. Fakes often have subtle differences — a different date font, a shifted coat of arms, a simplified design.

6. Where to buy safely

1. 1Buy from sellers with ratings and reviews — reputation beats a single deal.
2. 2For expensive silver/gold coins prefer slabs (a coin in a capsule with an NGC/PCGS grading certificate).
3. 3Compare the price to the market: a suspiciously cheap rare coin is often a fake.