Gemstone of the Month: Citrine

Citrine is the birthstone for the month of November. It is a quartz, and its chemical composition is silicon dioxide coloured with iron. It is not as flashy a gemstone as lapis lazuli, or malachite, or emerald, but it does have a quiet beauty all of its own.

It ranges in colour from light yellow to golden brown, and is only found in a transparent form. Natural citrine is rare, and most commercially available stones are actually heat-treated amethyst or smoky quartz; heat-treated stones nearly always have a reddish tinge to them, enabling the discerning to detect that the stones are not true citrines. Natural citrine is found mainly in Brazil, Madagascar and the United States, with minor deposits in Argentina, Myanmar, Namibia, Russia, Scotland and Spain.

Citrine makes lovely delicate unusual jewellery. See the Granary Knits store for these and other designs.

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Knitted onto silver wire, citrine chips make an attractive and unusual accessory

Gemstone of the Month: Tourmaline

Tourmaline is the birthstone of October. The name is derived from Sinhalese, Turamali (meaning stone of many colours); it was mined in Sri Lanka for centuries, but first imported into Europe by the Dutch in the early 18th century.

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Tourmaline is actually a group of gemstones, rather than a specific single stone (like lapis lazuli or peridot), and depending upon its colour its name can vary, from Achroite (colourless) to Verdelite (green). The chemical composition distinguishes the different forms of tourmaline; so Dravite is named after deposits found near the river Drave in Austria/Carinthia and contains magnesium; Elbaite is named after the island of Elba in Italy and contains lithium; and Tsilaisite is a local Madagascan name and contains manganese.

Tourmaline is found in a huge range of colours and is usually sold in mixed strings or bags, so that the jewellery made from it has a vibrant look and feel. The stones polish well, and the colouring is rich in each stone. Earrings made from tourmaline are unusual and intriguing!

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Simple but effective Tourmaline earrings, available in store
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Tourmaline earrings knitted using silver wire, available in store

Gemstone of the Month: Lapis Lazuli

Lapis beads in various shapes and sizes

The beautiful, rich blue Lapis Lazuli is the birthstone for the month of September.

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Of all the gemstones I have worked with over the years, I think Lapis Lazuli is my favourite. All gemstones have a certain something about them – the variations in colour, the surprise of interesting inclusions, the mystery of their origins – but lapis has something else, a sort of inner glow. The name is derived from Arabic, meaning blue stone, but there are lots of naturally blue stones and what is sold as lapis is not always lapis. Lapis is an azure blue (coloured by sulphur) rather than the deeper blue of Sodalite or the mid-powder blue of Azurite; it is lighter in colour than Dumortierite (which veers off towards violet-blue), and it is opaque, not transparent to semi-transparent like Lazulite. The best examples have an even colour distribution and some (but not too much!) well distributed inclusions of pyrite – looking like golden speckles within the stone.

Lapis beads in various shapes and sizes
Lapis beads in various shapes and sizes

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It has been mined for over 6,000 years in the Hindu Kush mountains of Afghanistan; in Russia it is found near Lake Baikal; in Chile it is mined north of Santiago. It has been used for jewellery since prehistoric times; in the Middle Ages in Europe it was used, ground up, to produce the pigment Ultramarine, an essential colour in mediaeval religious art; palaces and churches have lapis panels and columns, and are decorated with vases and urns sculpted from lapis. Today we still make rings, necklaces, earrings and bracelets out of it.

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Lapis Lazuli knitted earrings
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Lapis lazuli chips form a simple but effective earring

 

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Lapis Lazuli knitting stitch markers

Gemstone of the Month: Peridot

The beautiful translucent bright green Peridot is the birthstone of the month of August. It is also known by the names Chrysolite and Olivine. The best examples come from Egypt and from the Pakistan-Afghanistan border region. The intensity of the colour of the stone depends upon the amount of iron it contains. Its chemical composition is magnesium iron silicate.

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Peridot chips

The origins of the name ‘Peridot’ are obscure; some authorities say that it is derived from the Greek word peridona which means ‘giving plenty’; others that it comes from the Arabic word faridat, meaning gem.

Schumann notes that there are historically important deposits on the Red Sea island of Zabargad, where it has been mined for over 3,500 years; it is also found in Burma (Myanmar), Queensland Australia, Brazil, China, Kenya, Tanzania, and Arizona. It has even been found in Norway.

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Peridot earrings available in store