Amethyst – PLB050
Click on the "Add to Quote" button for pricing information. Check out "How to Purchase" and "Request a Quote" at the bottom of the page.
- Customized orders available
- Open Box option to combine shipping
- Payment by installments accepted
- International Shipping
Description
Beautiful Thunder Bay Amethyst from an undisclosed private location in the Thunder Bay area.
The Thunder Bay Amethyst occurrence is approximately 200km long along the Northern shore of Lake Superior.
The amethyst deposits of the Thunder Bay District are associated with the rocks of the Osler Group, formed during a late Precambrian stage of volcanism and faulting, from 1.2 to 0.9 billion years ago. In general, the amethyst deposits are in or near the granitic rocks, in proximity to the contacts between the rocks of the Osler and Sibley Groups. The faulting and related fracturing of these rocks during the late precambrian allowed for the intrusion of the fluids which ultimately led to the deposition of the amethyst crystals. These fluids precipitated the amethyst onto the walls of the fractures, creating crystal-lined veins and cavities. The faulting and fracturing – and therefore the nature and occurrence of ameythst-bearing veins – differs somewhat from locality to locality within the Thunder Bay District. Some brecciated zones are characterized by large numbers of relatively parallel small veinlets, while in other places much larger fractures are hosted by much more competent rock. (from https://www.davidkjoyceminerals.com/pagefiles/articles_thunderbayamethyst.asp)