Today I came across some lead glass ruby rings being sold with very misleading information – or lack of it. As a gemologist it saddens me that customers are still not being fully informed. Rubies are classed as type 2 stones due to the visible amount of fractures and inclusions found within them, it adds to their character and beauty. Jewellery quality rubies over 1 carat without any eye visible inclusions can be found, but are much rarer and harder to obtain. Ruby & sapphire are routinely heated. In fact 97% are routinely heat treated to improve colour and clarity. Because of the natural fractures inside ruby it was discovered in the 1990’s that whilst routinely heat treating ruby, it was possible to add lead glass to fill the fractures. This then became the treatment of choice for worthless unsaleable rubies. Once the ruby has cooled the lead glass sets and fills the fractures and therefore raises the clarity and the overall look of the stone. You can buy lead glass filled rubies for a few dollars per carat as these are non-durable stones. It is not a permanent treatment and it is not an industry accepted treatment either.
Have you ever wondered why a lot of jewellery stores (including Muscat Gems) sell pendants without chains? The main reason is that preferences for chains are just so varied. The main preference is chain length. Not everyone wants the standard 16" chain. I personally have several different lengths in gold and silver chains, as different items of jewellery need to sit at slightly different lengths. Then there is the actual design of the chain along with the weight and thickness. When you take all of this into consideration, it makes sense to take out the chain and just buy a pendant and then use one of your favourite existing chains.
The main purpose of gemology is to positively identify a gemstone using a range of scientific gemological instruments. It is possible to identify the different species and varieties of gemstones and separate them from the many types of synthetic and imitation material although, unfortunately, most of this equipment needs to be used on a loose stone. This does not mean we can not test a set stone, it just makes it a lot more difficult and in some cases virtually impossible to detect the many types of treatments that are being used on gemstones.
Each gemstone has its own specific gravity index which is basically the density of the stone. This unique index is one of the gemological tests we...
For pavé and micro pavé set stones. Soak your jewellery in a warm solution of liquid detergent and water. Rinse thoroughly with warm water. Use a lint-free soft cloth to dry. Never put pavé set jewellery in an Ultrasonic cleaner.
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