Crystals, raw or polished minerals

There are over 4600 different minerals, and new minerals are discovered every year. The definition of a mineral is that it is a naturally occurring substance in solid form, homogeneous, crystalline, inorganic, and defined by its chemical formula. If we break down the previous sentence, it might become even clearer what counts as a mineral.

A naturally occurring substance - minerals are created by the geological processes constantly at work in the Earth. How minerals are formed is a long and varied process involving different elements and reactions within the Earth, which in turn gives the stone its unique properties. Synthetic gemstones cannot be considered minerals as they are created in laboratories.

Inorganic - minerals do not consist of and are not created from animal or plant parts, so coral, pearls, and amber are not minerals.

Defined by its chemical formula - everything that exists is made up of atoms. A given quantity of a certain number of different types of atoms is what we call, for example, rock crystal; if the mass consists of other types of atoms, then it is a different mineral. The chemical formula for rock crystal is SiO2, meaning each silicon atom is linked to 2 oxygen atoms.

The definition of what constitutes a gemstone is not always clear-cut. Generally, it can be said that it is a material used for adornment and decoration. Most gemstones are minerals, though not all. Some examples of gemstones that are not minerals include amber and coral, and there is also a long list of gemstones that are man-made, such as synthetic diamonds and rubies. However, there are some criteria to follow to determine if a material is considered a gemstone: these are beauty, durability, rarity, and acceptance. We will explain these terms individually:

Beauty – that the material is beautiful in itself, or that it becomes even more beautiful with processing, such as polishing or cutting.

Durability – that the material is resistant enough to be processed to make it useful for adornment or decoration.

Rarity – for natural materials, there is always a limitation. Even though a manufacturing process is constantly ongoing within the Earth, we cannot influence which materials will form and in what quality we find them. It is for this reason that many coveted gemstones are produced synthetically. Synthetic gemstones are similar to natural ones, both chemically, optically, and physically, and are therefore sometimes very difficult to distinguish from natural ones.

Acceptance – it is the acceptance of a material that makes certain materials considered gemstones. Glass is not accepted as a gemstone, even though it can be beautifully cut and set in fantastic jewelry. It is also the acceptance of a material that makes certain materials more desirable and more expensive than others. For example, natural and untreated minerals are considered more desirable than their synthetic counterparts, even though manufactured stones are often many times more beautiful. The acceptance of a material also determines what we see in the market. An example of an unaccepted material is new ivory.

So what is the difference between a semi-precious stone and a gemstone?

The term semi-precious stone is outdated and misleading. Semi-precious stone suggests that the stone would be less valuable than a stone called a gemstone. However, in many cases, for example, a high-quality amethyst can be both more beautiful and more expensive than low-quality sapphires and rubies. Therefore, semi-precious stone is a term we avoid using.

The word "crystal" can mean several different things:

• Crystalline materials, which include all minerals (see heading "Minerals").
• Raw mineral that is untreated and where the crystal structure of the mineral is clearly visible. For example, natural rock crystal points.
• Polished crystal points in jewelry or to place on, for example, a home altar. These can be made of a mineral but also, for example, polished glass.
• Prisms and Swarovski crystals are polished glass but are also called crystal.