I collect star sapphires. It started in 1975 when I was living in Thailand, and took a trip to Ban Ploi in Chanthaburi province, and chatted with the workers as they dug holes in between the banana trees and scraped carborundum stones off the walls of these holes. Carborundum is the stone which is more commonly known as sapphire. Red carborundum is called a ruby. Some carborundum is infused with threads of titanium oxide, and when cut and polished correctly these threads reflect sunlight in a way which makes a star of light on the surface of the stone, and illuminates the whole gem, making it appear larger than it really is. The illusion fascinates me, I find the star hypnotizing.
The workers would not sell me the uncut carborundum, because they were required to sell to the gem exchange in the provincial capitol. So I went to downtown Chanthaburi and shopped for star sapphires there. And got some amazing deals on beautiful 1-carat stones. Being a poor starving Peace Corps Volunteer I only had $100 to spend, so my collection started very small. The next two trips in 1989 and 2005 I brought along more $$ and got more and bigger stones. The 2005 trip also introduced me to many fine shops which sold over the Internet, mostly through eBay stores, and I have been adding to my collection that way - it's a lot less expensive than air fare and unpaid leave to Thailand. Photos of most of my collection are online here. My last couple of purchases were lots of 20 stones, out of which about a dozen did not have enough of a star for me to keep in my collection. These are light blue, cabachon and round, about a carat, and I am offering them free to anyone who could use them for jewelry and/or costuming. Post a reply here and I'll divvy them up in a couple of days.