The rough and crystal topaz pictured above is certainly Australian topaz, but my source was not sure of the specific mineral district. I am almost certain it is Mount Surprise (QLD) topaz, although I have not seen a lot of material from this location. The material pictured has great clarity, the cut stone is a little included, as I cut it from a lesser quality piece as a first test cut. The quality of this topaz sure makes me want to have a fossick in this area.
As a side note, topaz at hardness 8 on the Moh’s scale is also the hardest of all the gem silicates. It’s harder than beryl gems (aquamarine, emerald, morganite, heliodor, goshenite) feldspar type gems, garnets, peridot, rhodonite, tourmaline, zircon, nephrite and jadeite. That’s impressive in my book.
I would love to hear from anyone who has visited Mount Surprise for gem fossicking, has first-hand knowledge of Surprise topaz, or anyone who has some rough material from this field available.