Blue gem Karambit and the bluest Case Hardened skins
Blue gem: A blue gem is a Case Hardened skin whose pattern is mostly blue. The name comes from players, not from Valve, and these copies usually sell for more than the rest.
Case Hardened
Case Hardened is a finish colour case-hardened with wood charcoal at high temperatures, according to its official description. It exists on the AK-47, the Five-SeveN, the MAC-10, knives and gloves; the current list is in the table below.
Why no two copies look alike
Every copy carries a pattern number, the “pattern template”, also called the seed. It sets the offset and rotation of the paint on the weapon. Two Case Hardened skins with the same name and wear can show a little blue or a lot of it.
Valve doesn’t publish a list of blue patterns. The lists going around are player-made rankings, and we don’t reproduce them. To know what you’re buying, look at the image and the pattern number on the listing.
What our prices tell you, and what they don’t
We record prices by market name, without the pattern. The price shown below is the lowest on sale for that name, and nothing says it’s a blue one. A blue gem is judged on the listing, not on the name.
Karambit | Case Hardened: where to find its price
The Karambit | Case Hardened price is on its own page, wear by wear, normal and StatTrak™, with the time of the reading. It’s the price of the name, not of a pattern: we don’t record patterns, so nothing says the cheapest copy is a blue one.
Each marketplace’s price, copy by copy: what each marketplace asks for this knife.
Case Hardened skins and what they cost today
Every Case Hardened family in the catalogue, with the range of recorded prices across all wears, StatTrak™ versions and patterns.
Most recent price reading: , Paris time.
Asking prices before fees, recorded on the marketplaces we track. They aren’t completed sales. “—” means not measured, never 0. How these prices are calculated
Sources
Before you pay, read what to check on the listing. And to see how much the same skin’s price moves from one marketplace to the next: the price gap index.