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Gem of the Month: Agate

The modern and traditional birthstone for September is Sapphire – covered in a previous article.  While sapphire is our primary interest, we also enjoy and appreciate the many alternative birthstones for each month.  The mystical birthstone for September is Agate – a stone of amazing variety and colour. Gemmology Matters:  Agate is the name given to […]

Gem of the Month: Sardonyx

This month’s gemstone is Sardonyx, the alternative birthstone for August (photograph at left from Thaigem).  The modern birthstone is peridot (covered in a previous article) but sardonyx has an ancient history and is a fascinating stone. Gemmology Matters:  Sardonyx is a variety of onyx which is a form of banded chalcedony (cryptocrystalline quartz or SiO2) or agate. The name […]

Gem of the Month: Bloodstone

The modern birthstone for March is aquamarine – see our March 2005 article on aqua for more information on this gem. However, the traditional birthstone for March is Bloodstone which has only recently been replaced by the more valuable aquamarine gems. However, bloodstone is a really interesting gem which is definitely worth a closer look. […]