Just want to give you guys the heads up, I am seeing a lot of so call hydro topaz on ebay.
This one said Hydro topaz on the packet when it arrived, but was just declared as "treated". What made me suspicious was the concave cut which seems to be a common trend, though not exclusively.
Attachment 4006
Topaz is one of the most common mineral so synthetics are not worth the effort and generally not manufactured, so my interest was immediately sparked.
The Hydro Thermal techniques is used to grow beryls and quartz( most so called "green amethyst" is this material) green quartz does exist but is general pale.
Anyway back to topaz, Topaz is generally natural, but more often that not treated ( this does not affect the commercial value) mostly blues are created, but pink can occur.
What is not generally regarded as acceptable is coatings. These rub off in time and are not regarded as permanent. Most common are pink and so called mystic.
So what is thus blue hydro topaz? Well all the samples i have seen have an ri of 1.5 and show no reaction in a Polariscope, meaning they are not crystalline !
Diagnosis : Blue Glass
