Hyalite Opal, Gallatin Co., near Bozeman, MT

Description

Hyalite Opal, Fluorescent, from Montana! Even though crusts of Hyalite Opal have been known from Montana for decades, good quality specimens are rarely seen on the market from the state. A new claim in Gallatin Co., MT, has recently produced specimens of a quality rare to the state, more reminiscent of classic Mexican and Hungarian Hyalite Opal. I will post a number of these pieces in the upcoming period.
This piece is 2inchx2inch in width, and o.4 inch in height. It's weight is 46 grams, or 15/8th oz. It has a sawed base, to improve it's display quality. Interestingly,, it has two more generations of formation, both non fluorescent, but associated with Opal and/or hydrothermal volcanic activity, the upper white crust is "Sinter", or sometimes called "Geyserite", below that a different mix shape of opal, or Opalite. At the same time, the Hyalite forms a nice crown, all around. super interesting piece! And, as with the other pieces from this locality I sell...they have been rinsed, but could be cleaned more thorough...
The here presented example is great for the species, as well as Montana as a locality, but also for collectors of Fluorescent minerals. Apologies for the poor photo's, as Hyalite is difficult to photograph, short of a professional photography set up, leave alone out of hand with a Phone camera....
However, as the photo's show, this is great Hyalite, perched in the center of it's host rock, which is Basalt. As shown, Hyalite is very Fluorescent under Shortwave UV, and displays a vivid lime green glow.
Please be advised, I ship with Parcel Select.