What is a “karat”? The purity of gold is measured in karats, with the purest possible form of gold being 24 karats. Eighteen or 14 karat gold is most commonly used.  Generally, jewellery is stamped with its karat measure – or with the corresponding metric measure, which reflects the percentage of gold in the piece, with “1.0” representing pure gold (or 24 karats). Some karat marks are unusual in Canada – such as 9kt. If you see a 9 kt mark on a piece of jewellery, it was probably made in another country— or it may be an antique.

Here are the standard karat markings, along with their corresponding metric equivalents:

9kt or .3750

10kt or .4167

12kt or .5000

14kt or .5833

15kt or .6250

18kt or .750

19kt or .7917

20kt or .8333

22kt or .9167

24kt or 1.000

What exactly is gold? Gold has been used since ancient times as form of wealth and adornment. It is one of the earth’s elements, and it is both extremely ductile (and thus easy to mould and work) and resistant to tarnish & corrosion. It is also very beautiful.  Gold can be alloyed into different colours (white, pink, red and green) by adding different metals to it. New alloys are constantly researched to create a whiter white gold, or a richer pink. Gold is an excellent metal for jewellery of all kinds. It takes a high polish and is sufficiently rigid to withstand many years of use and hold gemstones securely.

What is Platinum? Platinum is a white metal that is very dense (21.5 specific gravity) that is highly resistant to corrosion. Platinum’s hardness ranges from 4 to 4.5, and it is ductile. While it is quite hard it can bend out of shape, especially if it is a narrow band. Over years of wear, platinum develops a patina of fine scratches; this giving it a gray/white hue. This metal was very popular in the 1920s and 1930s, and has enjoyed a recent return to fashion.