There have been more developments in gemstone treatments in the past 15 years than in the previous 50, and many of these concern sapphires and rubies.

There are many myths and misconceptions in the gem and jewellery world. Some are found on the internet, some have bizarre origins in history and some, unfortunately, are believed even by people in the industry. Here are a few of the more common ones.

Lead glass-filled rubies, currently available in large numbers in Australia, are causing serious issues for jewellers, suppliers and retailers alike.

The diamond market, as any retailer will tell you, is tough. There’s competition from not only fellow “bricks and mortar” businesses but also virtual stores on the internet. Some jewellery retailers are finding that one way to boost their overall profitability is to look at increasing their coloured gemstone sales. Coloured gems offer retailers a greater margin for a number of reasons.

An Australian jewellery supplier says eBay should clean up its act and rid the popular website of misleading and disreputable jewellery sellers.

The minerals and rocks known collectively as the ornamental gemstones are grouped together because they normally lack transparency. They owe their attraction to the colour, texture or pattern they possess. Often, it can even be a mix of these qualities.

Throughout history, quartz has been recognised as the chameleon of gemstones, substituting for an incredibly diverse range of more expensive gemstones from diamond to jade; however, in recent times, the incredible variety of quartz is being appreciated for its own sake.

Diamonds are the most popular of all gemstones, desired for their beauty, their unusual attributes and the myths and legends attached to them. It goes without saying that well-cut diamonds displaying fire and scintillation are considered by many to be the most beautiful gems.

So much of gemmology is about correct terminology. In this on-going series, Jeweller talks terms.

Deep red is generally the colour that comes to mind when thinking of garnets. The use of garnet dates back to biblical times, with several references to the gem in the Bible. Legend has it that a large garnet adorned a pedestal in the middle of Noah's Ark. The brightness of the stone was said to illuminate the sea, allowing the ship to travel safely through the night.

Australia’s national gemstone is also one of the most complicated to cut. GAA opal experts Anthony Smallwood and John Krook explain why it is an art form in its own right.

Cat’s eye and star gems are prime examples of how inclusions can be an asset in coloured gems rather than a liability, explains the GAA’s KATHERINE KOVACS.