Synthetic Glass (Often categorized as a simulated mineral)

Goldstone (Red)

Aventurine Glass (SiO2 + Cu)

Hardness: 5.5-6 (Mohs); Color: Reddish-brown with metallic sparkling inclusions; Luster: Vitreous to metallic; Crystal Structure: Amorphous (glass) with octahedral/triangular copper crystals; Specific Gravity: 2.5-2.8

Hardness: 5
Color: Reddish-brown with metallic sparkling inclusions
Luster: Vitreous to metallic

Identified March 21, 2026More synthetic glass (often categorized as a simulated mineral) →

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Physical properties

Formation & geological history

Goldstone is a man-made material produced in a low-oxygen reducing atmosphere. It was originally created in 17th-century Venice (Murano) by the Miotti family. The process involves dissolving copper oxides into molten glass, which then crystallize into tiny metallic flakes upon slow cooling.

Uses & applications

Primarily used for decorative purposes, including jewelry (beads, cabochons), carvings, tumbled stones for collecting, and metaphysical uses (reiki/healing crystals).

Geological facts

Legend says it was discovered by accident when Italian monks spilled copper filings into a vat of molten glass, though the Miotti family held the official patent. It is often confused with the natural mineral Sunstone, which has a similar appearance but different chemistry.

Field identification & locations

Identify by looking for a consistent, deeply saturated reddish-brown glass matrix filled with tiny, highly reflective, uniform metallic triangles or squares. Unlike natural minerals, it contains no natural air bubbles or irregular inclusions and won't be found in raw geological outcrops; it is essentially universal in gift shops and crystal markets.

Other synthetic glass (often categorized as a simulated mineral) specimens

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Synthetic Glass (Simulated Opal)

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Opalite

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Opalite

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Cat's Eye Moonstone (Simulated/Synthetic or natural Cat's Eye Quartz/Glass)

There is no single scientific name. The appearance suggests either: Moonstone (feldspar group), Cat's Eye Quartz (SiO2), Apatite (Ca5(PO4)3(F,Cl,OH)), or most likely a synthetic material such as Fiber Optic Glass or 'Opalite' (a type of glass).

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