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.

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.

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.

Silversmiths, goldsmiths, and lapidaries methods include forging, casting, soldering or welding, cutting, carving, and "cold-joining" (using adhesives, staples, and rivets to assemble parts).Diamonds:Diamonds were first mined in India. Pliny may have mentioned them, although there is some debate as to the exact nature of the stone he referred to as Adamas; In 2005, Australia, Botswana, Russia and Canada ranked among the primary sources of gemstone diamond production.

Although artistic display has clearly been a function of jewellery from the very beginning, the other roles described above tended to take primacy. It was only in the late 19th century, with the work of such masters as Peter Carl Faberge and Rene Lalique, that art began to take primacy over function and wealth. This trend has continued into modern times, expanded upon by artists such as Robert Lee Morris and Ed Levin.

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.

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.

Many items of jewellery, such as brooches and buckles originated as purely functional items, but evolved into decorative items as their functional requirement diminished. Jewellery can also be symbolic of group membership, as in the case of the Christian crucifix or Jewish Star of David, or of status, as in the case of chains of office, or the Western practice of married people wearing a wedding ring.