Stones are conventionally distinguished as either precious or semi-precious. It is today considered meaningless – not to mention confusing – to categorise natural stones based on value rather than beauty and rarity. The term ‘natural stone’ covers stones, minerals, crystals and organic gems found in nature.
Gemstones are divided into smaller subcategories based on species and groups. A gem species is a broad gem category that encompasses gemstones that share common qualities. Gemstones of the same species all have an identical chemical composition and structure and can be further divided into different varieties based on factors such as colour, transparency or phenomenon (optical effect).
Quartz is the gemstone species with the largest number of different gemstone varieties linked to it. Gemstones are formed naturally in nature, without human intervention. Most are minerals - natural, inorganic materials with a specific chemical composition – and a small proportion of gemstones are rocks. Additionally, some gemstones are organic, produced by living organisms.
Gemstones are stones formed in nature over thousands of years. The perception of what is considered a precious gem is mainly based on a gem’s rarity – something that has changed throughout history. The amethyst used to be considered a precious stone by many cultures for thousands of years, but a recent discovery of new deposits dramatically decreased the value of the stone, which is now considered semi-precious.
In this chapter we will not distinguish between precious and semi-precious but rather take a look at the overarching category of ‘natural stones’ used in Pandora jewellery.
