Quartz and Corundum

February 2016 is upon us already. Where did January go? For me, it was spent in learning new things, doing new things and preparing for new things-exciting and fun times. It is two weeks till Valentine’s Day and maybe I should be talking about diamonds but as I am about to teach a Diamond Grading course for the Canadian Gemmological Association, I think I would like to talk about something else.

February birthstone is Amethyst and I have written about it before,  however, since it is the birthstone let me mention  it again. Amethyst is the purple stone of the quartz family. Quartz is a species of gems that comes in a variety of colours and crystal habits with its chemical formula being Silicon dioxide (SiO2). The hardness of quartz is 7 and for you this means that it is hard-at least hard enough amethystto be used on a fairly regular schedule of wearing.  As there is silicon dioxide in the air,  we need to have the gems we wear be of equal or greater hardness to stand up against  constant wear over time.

Another colourful species of gems is corundum. You may know it better as sapphire and ruby but did you realize that sapphire comes in a rainbow of colours as well. IMG_0112 I was extremely fortunate to be given the opportunity of sorting some rough corundum from the gravel it is found in after it was mined.

The chemical formula for corundum is aluminium oxide ( Al2O3) and it is impurities that create the different colours.  It has a hardness of 9 which is right below diamond although a great deal below its hardness of 10.  The lustre of corundum is  vitreous to adamantine and thus very bright which only adds to its beauty as a gem species.

The photo on the left is some rough sapphires from a mine in Montana.   It is always an interesting day when you deal with gems as they are never the same. Gems are beautiful, colourful and tell a world of stories if you only know how to look.

Enjoy your month, don’t forget your loved one on Valentines day and call your local independent  jewellery appraiser for all your jewellery appraisal needs.

Till next month

Karen

Advertisements

One thought on “Quartz and Corundum

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s