The next most popular quartz gems are rock crystal, smokey quartz and rose quartz. Rock crystal is a colourless gemstone and has been used in jewellery for centuries. Pliny the Elder reported that rock crystal was ice that had been permanently frozen. The name ‘crystal’ comes from the Greek for ice, ‘krystallos’.
It can easily be mistaken for glass. One easy test to ensure that an item is rock crystal and not glass is to place it over some printing. The rock crystal will magnify the writing while the glass has no effect. This magnifying effect was used to enhance pieces of jewellery in cases like reverse crystal jewellery. In the brooch below, the painted insects are magnified by the rock crystal dome over them.
Similarly, ‘pools of light’ jewellery, which was popular in particular in the Edwardian period from 1900 to 1914, used this effect. This jewellery involved the use of crystal quartz as simple un-drilled balls or domed halves. Pieces like this were described as being ‘pools of light’ because of the way the light reflects through the gem. Sometimes the light passing through results in the gem glowing almost white. They will also render anything viewed through it upside down and in reverse. They were often designed as two halves of a locket so that a photo placed inside the two halves would be magnified, as in the case of the locket below, which contains a tiny flower from a rosemary bush.
Smokey quartz comes in the colours of brown, a smokey yellow and dark brown. It is also known as cairngorm, named after the Cairngorm Mountains in Scotland where it was mined. It was used a lot in Victorian pebble jewellery.
Rose quartz is a lovely pale pink gemstone. It usually has a lot of internal clutter – fissures and suspended matter. It is used for cabochons and beads, sometimes earrings and pendant. The photo at the top of the post of the vintage Chinese silver brooch and the one below of a bracelet are good examples of how it is used in jewellery.