How Fake Moldavite is Made

The most common production techniques are four: hydrofluoric acid, drilling, sculpting with a rotary tool, and mold casting. They are often combined to make the fake more credible. Let's look at them one by one.

01Hydrofluoric Acid

This is the most common way to "sculpt" green glass and imitate the natural surface of moldavite. Hydrofluoric acid selectively dissolves parts of the glass, completely changing its appearance. Traces of paint and wax have also been found on analyzed fake specimens: these were used to cover certain areas of the glass to achieve an irregular sculpture and greater variation between pieces, so they wouldn't all look identical.

02Drilling

Observing these fakes with a strong magnifier reveals drill marks and hydrofluoric acid residues. Drilling is used to create depressions and holes that mimic natural cavities, but it leaves unmistakable traces under the lens. Below are some examples, including a drilled fake moldavite sold in France.

03Sculpting with Jeweler's Tools

With a small rotary jeweler's tool, light grooves and "paths" are engraved on the surface, after which everything is refined with hydrofluoric acid to soften the contours. The result? Moldavite that often appears too perfect, with a uniform and repetitive sculpture, far from the irregular variety of natural moldavite.

04Mold Casting

Here, molten glass is poured into a mold — often taken from a real moldavite — and allowed to cool, resulting in a moldavite-shaped glass. A grinder then cleans the edge where the mold leaves junction lines. Molds allow many shapes to be reproduced, from primary forms (like drops) to fragments, but the result appears unnaturally perfect.

The most useful sign: if you find multiple sellers with the exact same piece, or a store selling several identical copies, it's proof that it was created from a mold — therefore fake.

05The Signs that Betray a Fake

• Drill marks or regular grooves visible under magnification.
• Traces of paint, wax, or acid residues on the surface.
• Sculpture that is too uniform or "perfect," without the randomness of natural pieces.
• Smooth edges and surfaces typical of molded pieces.
• The exact same piece sold by multiple sellers or in multiple copies.
• Excessive and uniform shine.

To learn how to distinguish real from fake step by step, see how to recognize authentic moldavite, identify real or fake moldavite, and our gallery of fake moldavites. Also discover the history and future of fake moldavite.