December Birthstones

Wednesday, 5 December 2018  |  Cristalmundo

December Birthstones

Three Birthstones - beginning with "T"

There are actually three birthstones associated with December: Blue Topaz, Tanzanite, and Turquoise.

Apart from starting with the letter “T”, all three of these stones have something else in common, and that is the colour blue – different shades of blue, but blue is definitely December's colour!

Blue topaz actually comes in different shades as well: Sky blue (the palest), Swiss blue and London blue (the deepest shade).  The question is often asked, is blue topaz a real gemstone? Natural blue topaz is quite rare, do colourless or pale material is heat treated and irradiated to produce the deeper blue colours described above.

Tanzanite, is a purplish/deep blue colour, and as the name implies, it is only found in Tanzania.  This means it is in limited supply and therefore one of the more valuable semi-precious gemstones.  It was first discovered in 1967, in one location, and as reserves of this mineral are diminishing, and replenishment seems unlikely, the perceived value of the stone is increasing and so is the demand!

Turquoise, that is, the genuine article, is also becoming scarcer. It is generally acknowledged that the best turquoise comes from various mines in Arizona, although it is found in other areas of the world as well, it is not quite the same quality.  It can be expensive. sometimes very expensive.  If you see items of turquoise jewellery that are quite cheap, then they can’t be the genuine natural thing.  There are many imitations and derivatives of natural turquoise. Glass imitation turquoise has been around since Victorian times, and so has enamel.  Other stones, such as Howlite and Chalcedony, can be dyed and stained to imitate turquoise.

Apart from imitations, there are numerous treatments which can be applied to turquoise.  For example, reconstructed turquoise uses turquoise powder or small chips which are bonded together with liquid plastic resin, then dyed and baked hard.  Reconstructed turquoise is much cheaper than natural turquoise but to the non-expert, it may look indistinguishable.

Turquoise is quite a soft stone and can be very porous and fragile so to make it easier to work with, it is nearly always stabilised or coated in some way to make it more robust. This type of treatment is effected at source and does not affect the price.

Enhanced turquoise is turquoise that has been colour-enriched by dyeing or staining. Turquoise that is enhanced and dyed is likely to be much cheaper than natural turquoise.  Turquoise is generally blue/green in colour although it can also be a sea green colour. 

Turquoise jewellery is quite delicate and should always be removed before washing (especially rings).  It should be stored in acid-free tissue paper in a cool, dark container, away from other jewellery that could damage it.  

We hope you have found this information useful.  Don’t forget to check out our blue topaz jewellery here