As I have seen over the past years, a lot of eBay buyer are cheated by overseas dealers by selling them Corundum or Corundum wannabe material.
Corundum is the general name for sapphires and rubies.
This guide is regarding sapphires.
Before you read this guide, please be sure that calling a sapphire Kashmir blue doesn’t mean it’s Kashmir, only a certificate from a reputable gem lab will guarantee you origin. Almost all sapphires on eBay claiming Kashmir are saying in the description that the origin is Ceylon.
There are a few types of sapphires:
Sleepy silky deep blue from the Kashmir Pakistan/India region, the mines are in the Pakistani side, hence it’s overrun by terrorists so mining operation is virtually gone there. Not to mention the mines haven’t produced in over 100 years.
A Kashmir sapphire can bring from over $1000 per carat to $75,000 per carat. Most sizes are small…
Basically you will not find any of these sapphire on eBay b/c they bring top $$$ between collectors and dealers, so anyone claiming Kashmir without a reputable certificate is lying.
Burma or Myanmar
Sleepy silky deep blue to crisp blue from Burma, these sapphires are 2nd to Kashmir stones, they are very sought after and are still mined. Large stones over 15 carats bring top dollars.
A Burma sapphire can bring from over $1000 per carat to $25,000 per carat. Size is not a problem, but Burma stones have strong color zoning so you have to watch out for quality or it might be worth much.
Ceylon or Sri Lankan
Light to deep & vivid crisp blues from Sri Lanka, these are the most beautiful of sapphires (as far as I am concerned), they come in a variety of sizes and colors so prices are affordable. Some stones run from around $50 per carat up to over $20,000 per carat for large and fine sizes.
African & Madagascar
These sapphires are very similar to Ceylon stones in many aspects and prices. Most stones tend to be much cleaner but for some reason they tend to be mostly cheaper to comparable Ceylon since most buyers are looking for Burma or fine Ceylon.
This is a new material which resembles sapphires, however it is not. eBay is flooded with the stuff and many people are buying sapphires which are not sapphires. Most of these sapphire wannabe stones are funneled through Thailand and India b/c that’s where they are mostly cut.
Last but not least….Laser diffusion….
This is a treatment where colorless Corundum is heated to a melting point and introduced to dye in order to give it color. These are worthless stones and like Kyanite, they are all over the place. Don’t fall for the old switch & bait Asian dealers out there…save your money and demand a real certificate or just pay normal prices from a local jeweler.
Reprinted from eBay user 47ddc