Diamonds, Diamonds, Diamonds, Everywhere There Are Diamonds
One man's quartz is another man's diamonds.
There was a prospector who called me from the field and wanted to know what he should do with all of the diamonds he had found. I was impressed: "How many did you find?" I asked.
"There are thousands all over the hill side!" He responded.
Now I knew something was not quite right. I asked him, "how are you verifying these diamonds?"
"I just scratch the windshield of my truck, and most of them leave a nice scratch".
I responded, "Can you see out of your window well enough to drive home?"
By the way, diamonds will scratch windshields, but since glass has a hardness of only 5.5 to 6 on the Moh's scale, many things will scratch your windshield including pyrite, feldspar, corundum and of course quartz. How do you think people get all of those pits you your windshield during sandstorms?
Then there was the prospector who called and said that he had been diamond hunting for years and never found any diamonds. After talking awhile, he mentioned his method for diamond testing: "I simply put them on an anvil and hit them with a hammer!"
He mentioned he had picked up some octahedral crystals in the Colorado-Wyoming State Line district (where there are several known diamond deposits) but none were diamonds because they failed his test!
I then told him about the difference between hardness and mechanical brittleness and that all diamonds will break when struck with a hammer.
You could hear that sound of ... well, it sounded like muffled swearing in the background as he hung up.
Some fancy diamonds from the Argyle mine, Australia. How valuable are these? Well some of the extraordinary pink to red diamonds are nearly priceless and sell for as much as US$1 million/carat (or many thousands of times more than an equivalent weight of gold).
Speaking of diamonds. Have you ever heard of the Ekati diamond mine in Canada? Most people are still unaware that Canada is now a giant in diamonds - just like South Africa. The have several diamond mines and just one of them, the Ekati, produces 3 million carats per year.