what is a herkimer diamond

What is a Herkimer Diamond? (The "Fake" Gem Worth Real Money)

If you’re digging in New York (or buying from a rock shop) and you see a crystal that is water-clear, super shiny, and has points on both ends, you’ve found a Herkimer Diamond.

But here’s the kicker: It’s not actually a diamond.

1. The "Identity Crisis" (Quartz vs. Diamond)

The name is a bit of a marketing trick from the 18th century.

  • The Truth: A Herkimer Diamond is a world-class Quartz crystal.

  • The Difference: Real diamonds are made of Carbon and formed deep in the Earth's mantle. Herkimers are made of Silica and formed in shallow pockets of 500-million-year-old limestone.

  • The Hardness: On the Mohs scale, a Diamond is a 10. A Herkimer is a 7.5. (Most regular quartz is only a 7, making Herkimers slightly harder and "sparklier" than your average backyard rock).

2. Why is it "Double Pointed"?

Most crystals grow attached to a solid rock wall, so they have one "pointy" end and one "broken" end where they were pulled off.

  • The "Floating" Secret: Herkimer Diamonds grew inside soft, clay-filled pockets (called "vugs") in the rock. Because they weren't attached to anything, they grew points on both ends.

  • The Search Term: In geology, this is called being "Double Terminated." If you find a crystal like this, don't try to "fix" the ends with your Dremel—the natural points are what make them valuable!

3. The "Black Pepper" Spots (Anthraxolite)

A very common Google search is: "Why are there black spots inside my crystal?"

  • If you look closely at a Herkimer, you might see tiny black specks. That isn't dirt; it's Anthraxolite. It’s basically 500-million-year-old fossilized sea plants.

  • Pro Tip: Collectors actually love these "inclusions" because they prove the stone is a genuine Herkimer and not a lab-grown fake from a factory.

4. Can You Find Them Outside of New York?

While the "true" Herkimer Diamond is only found in Herkimer County, NY, similar crystals (sometimes called "Pakimers" from Pakistan or "Arizona Diamonds") exist. However, the New York stones are famous for being "Water Clear"—meaning they look like a drop of pure water frozen into a stone.

5. Using Your Dremel on a Herkimer

Since you’re already a pro with the Dremel, here is how you handle a "Herk":

  • Don't Grind: You almost never want to "cut" a Herkimer. Its value is in its natural 18-faced shape.

  • The "Cleaning" Buff: Often, these crystals come out of the ground with a "skin" of white calcium or gray limestone. Use your Dremel with a soft brass brush or a felt wheel with polishing compound just to "brighten" the faces.

  • The Goal: You aren't changing the rock; you're just washing its face so the light can get in.

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