February Stone

•February 19, 2012 • Leave a Comment

Across my desk….

the other day came a delicious (is the only word to describe it) amethyst, which as many of us know is the birthstone of February and the stone of the zodiac sign, Pisces.

Amethyst is probably the most interesting and well known stone of the quartz family and when you see a fine speciman you  appreciate how underrated these stones are.

The word amethyst is an ancient derivation  – Pliny said it was called this as the colour was very close but not quite to that of wine.  The word is said to be derived from the Greek word Amethustos.  Which means ‘not drunken’.  It was supposed to protect from a binge drinking session where one usually gets hammered.  Hmmmmm.

One often sees pictures of them lining the hollow cavities of geodes.  If you visit museums or minerals shops there are usually some of them on display.  Sometimes they vary in colour from deep coloured – grading into a milky quartz or a rock crystal (colourless).  Sometimes you see them with yellowy/orange zones – these are called ametrines, a variation of citrine and amethyst.  Amethyst may be heated to produce citrine.  Some of the more interesting inclusions found in amethyst are banded structures known as ‘tiger stripes or ‘zebra stripes’.

Some Gemmology:  Amethyst is silicon dioxide SiO2.  Crystal System: Trigonal, Uniaxial positive, RI 1.53to 1.56 DR 0.009, SG 2.6 to 2.65.

Amethyst is a lovely stone but not very hard at MOH 7 (same as a hard steel file) – this can abrade fairly easily over time and wear.  Should not be worn as an everyday ring.  Avoid leaving amethyst in strong light as the colour may fade.

Note:  the stone pictured is not the one that passed my desk.  This is one taken from a google search to represent a typical colour of a nice amethyst.

Snap Happy

•November 24, 2011 • Leave a Comment

Well today was the day the photographer came. And when I looked around the room to decide where best to be seated for the ‘shot’ all I could see was gemmo paraphernalia from one end of the office to the other end. Granted the room is still not quite finished having its makeover, but there were books and pieces of equipment all over the place. And the walls are wallpapered with gemmology posters and articles, so the photographer faced his first challenge in finding a space to sit me without competing with the busy room. I am normally a fairly tidy and orderly person so all this mess is driving me crazy. Needless to say we achieved success and after about 100 photos !!! he left very happy. Probably 90 of them will be with eyes closed. Oh well I only need one to replace what is there now. So in a day or two you may see a new photo of me with a microscope. Another step closer to completion of rennovations and a tidy and well ordered office (as a Gemmologists office should be!).

Hello from Jill

•November 21, 2011 • 1 Comment

This is just a quick greeting before I really get started.

This is my new blog and I am really looking forward to giving you an insight into what I do on a day-to-day basis, as a professional Jewellery Valuer and Gemmologist.

I very much welcome your comments and interaction once I am up and running.

In the meantime, why not head over to my brand new website and take a look at what I do.
You can find the site here: New Zealand Jewellery Valuations Ltd

Kind regards