Some gemstones (like pearls, coral, and amber) are classified as organic, meaning that they are produced by living organisms. Others are inorganic, meaning that they are generally composed of and arise from minerals.

Jade: Jade is most commonly associated with the colour green, but can come in a number of other colours as well. Jade is closely linked to Asian culture, history, and tradition, and is sometimes referred to as the “stone of heaven.”

Other commonly used materials include glass, such as fused-glass or enamel; wood, often carved or turned; shells and other natural animal substances such as bone and ivory; natural clay; polymer clay; and even plastics. Hemp and other twines have been used as well to create jewellery that has more of a natural feel. However, any inclusion of lead or lead solder will cause an English Assay office (the building which gives English jewellery its stamp of approval, the Hallmark) to destroy the piece.

These high purity alloys, however, are widely used across Asia, the Middle East, and Africa. Platinum alloys range from 900 (90% pure) to 950 (95.0% pure). The silver used in jewellery is usually sterling silver, or 92.5% fine silver. In costume jewellery, stainless steel findings are sometimes used.

Form and function:Most cultures have at some point had a practice of keeping large amounts of wealth stored in the form of jewellery. Numerous cultures move wedding dowries in the form of jewellery, or create jewellery as a means to store or display coins. Alternatively, jewellery has been used as a currency or trade good; an example being the use of slave beads.

Jewellery has been made to adorn nearly every body part, from hairpins to toe rings and many more types of jewellery. While high-quality jewellery is made with gemstones and precious metals, such as silver or gold, there is also a growing demand for art jewellery where design and creativity is prized above material value. In addition, there is the less costly costume jewellery, made from lower value materials and mass-produced. Other variations include wire sculpture jewellery, using anything from base metal wire with rock tumbled stone to precious metals and precious gemstones.

Amethyst: Amethyst has historically been the most prized gemstone in the quartz family. It is treasured for its purple hue, which can range in tone from light to dark. Emerald: Emeralds are one of the three main precious gemstones (along with rubies and sapphires) and are known for their fine green to bluish green colour. They have been treasured throughout history, and some historians report that the Egyptians mined emerald as early as 3500 BC.

Most American and European gold jewellery is made of an alloy of gold, the purity of which is stated in karats, indicated by a number followed by the letter K. American gold jewellery must be of at least 10K purity (41.7% pure gold), (though in England the number is 9K (37.5% pure gold) and is typically found up to 18K (75% pure gold). Higher purity levels are less common with alloys at 22 K (91.6% pure gold), and 24 K (99.9% pure gold) being considered too soft for jewellery use in America and Europe.