Other places have turquoise, but not nevada-grade

What’s black and blue and lumpy all over?

Nope, we’re not talking about Miguel Cotto’s face after 12 rounds with Manny Pacquiao.

We mean Nevada’s official semiprecious gemstone — turquoise.

“If you look at what gems the state of Nevada has that are valuable, far and away, turquoise would be the biggest,” said Chris Ralph, associate editor of Prospecting and Mining Journal.

Nevada’s land has yielded millions of pounds of turquoise, Ralph said, but he estimated the state produces 3,000 to 5,000 pounds a year these days. And practically all of it goes to jewelry.

The Silver State has lots of turquoise thanks to its arid environment and geology. As the occasional desert rain filters through Nevada’s mineral-packed dirt, it leaches out and combines turquoise’s key ingredients — copper, aluminum and phosphate. It takes thousands of years of the rain-and-dry cycle to forge a vein of turquoise. The biggest chunk ever mined in Nevada was a 500-pound nugget found in the 1950s near Carlin, in Northern Nevada.

The state has “quite a bit” of turquoise left, Ralph said, but a good number of deposits run alongside silver and gold trends, so they are being mined for their precious metals instead.

What’s more, the turquoise business just isn’t what it was in the 1960s and ’70s, when the stone was fashionable for its earthy nature. Plus, there is more competition today from upstarts such as China, which Ralph said is marketing lower-grade, porous turquoise shot through with resins to make it as durable as Nevada’s version. Plasticized turquoise isn’t nearly as valuable.

“Nevada has the highest-quality stuff, and it’s ready to use as it comes out of the ground,” Ralph said.

Ralph even offered a trick to help you tell the difference: Heat a straight pin until it’s red-hot, then touch it to the turquoise. If it makes a burn mark or smells like plastic, you’ve got an inferior stone. If the hot pin does nothing, you’ve got yourself some Nevada-grade turquoise.