There are also many gemstones that are not true minerals, but which are gemstone varieties of recognized minerals.Ī few gemstones are mineraloids (not true minerals) such as opal, amber, and moldavite. A few gems are oxides and only one gem, diamond, is composed of a single element, carbon. All gemstones have some characteristics falling short of perfection though even the seemingly perfect Diamond. Most gems are silicates which can be very stable, hard minerals.

Most gemstones have good hardness (above 5) and a high index of refraction (the higher the index of refraction the greater the sparkle). Others are too common and are given a semi-precious status. Some minerals can be very beautiful, but they may be too soft and will scratch easily. Generally speaking, a gemstone is a stone that is beautiful, rare, and durable (resistant to abrasion, fracturing and chemical reactions).

There are over 3,000 different minerals, but only about 50 are commonly used as gemstones! So what makes a gemstone?

Hearts of iron 4 uncut