Gemstones have been prized for thousands of years for their colour, clarity, rarity, shape and durability. They are made from minerals that form in many different geological situations. Gemstones are cut and polished to enhance their natural beauty and remove imperfections. The smooth facets created in this way help to transmit and reflect light.

Some gemstones are more valuable than others. Depth and evenness of colour are important, and intensely coloured stones are especially sought after. A gemstone’s colour depends mainly on its chemical composition. In some gemstones the main element causes the colour; for example, turquoise — copper phosphate — is coloured blue by the copper. In other gemstones, very small amounts of an element cause the colour.

Museum Victoria’s collection of faceted gemstones and polished ornamental rocks has been acquired since the 1860s. New discoveries mean there are many more minerals used as gemstones now than in the past. Significant contributions to the gemstone collection have been made recently by Peter Hoppen, Murray Thompson, Ron Perrin and Grant Hamid.