This is the classic in the world of pearls. Akoya pearl was the first type of pearl that could be successfully cultivated. Cultivation started at the beginning of the twentieth century. Nowadays most of these pearls come from Japan. China and Vietnam are secondary sources. The Akoya pearl oyster (Pinctada martensii) is used to grow Akoya pearl; cultured Akoya pearls are generally between 2 and 9 mm in diameter, and they are particularly attractive due to their intense shine and their wide spectrum of pale shades, ranging from white to pink to cream and silver gray.

An alloy is a metal mixture consisting of two or more components. Alloys are named after their base metal. Some attributes of the base metal can be improved by melting it into an alloy. Pure gold would be too soft to use as a jewel metal; Mixing it with other metals to create a gold alloy makes the resulting metal harder and more practical to wear as jewelry. Metals that are often included in gold alloys include silver, palladium, and copper. These additions also affect the color: silver makes gold paler; Copper gives a reddish hue. The color spectrum for gold alloys varies from white to greenish-yellow to red. The amount of base metal contained in an alloy is expressed in carats.

When the Greek god Dionysus became all too insistent on looking for a nymph named Amethyst, the girl was transformed into a sparkling gem by the goddess of chastity. This is the story that Aristotle tells to explain the origin of amethyst and its supposed ability to protect the wearer from drunkenness. This protective attribute is also the origin of the name of the stone: the Greek word "améthystos" means "not drunk". Amethyst belongs to the quartz group and has a rich shade from purple to pale red-violet. Heat treatment changes color (see citrin). The most important sources of amethyst are in southern Brazil, Uruguay and Madagascar.

According to the legend, aquamarines come from the coffers of mermaids. The stone's name comes from Latin and means 'water of the sea'. It earns this name through its vivid, shiny hue, ranging from pale blue to deep blue and blue-green. The most avidly sought-after hue is deep blue. An aquamarine of this colour is also known as a 'Santa Maria'. Aquamarine belongs to the beryl group. Brazil and Madagascar are the most important sources.