CS2 Case Hardened & Blue Gem Skins
Case Hardened skins are tinted by a paint seed (one of 1000 patterns) that fixes the blue, gold and purple layout. Seeds with heavy blue on the playside are the prized "Blue Gems".
On the AK-47 the reference Blue Gems are seeds like 661, 670 and 955; on the Karambit it is seed 387. Top patterns sell for many times an average Case Hardened. Open any skin below to compare prices and read its pattern.
All 24 skins
Updated 1 h ago
Karambit (Case Hardened) Covert $609.70 27 markets -2.6% 628 /day ST
Butterfly Knife (Case Hardened) Covert $569.95 30 markets -1.4% 1.2K /day ST
M9 Bayonet (Case Hardened) Covert $441.02 28 markets -2.6% 711 /day ST
Talon Knife (Case Hardened) Covert $353.57 29 markets +0.5% 994 /day ST
Bayonet (Case Hardened) Covert $212.35 28 markets -2.5% 898 /day ST
Skeleton Knife (Case Hardened) Covert $203.59 30 markets +4.8% 824 /day ST
Stiletto Knife (Case Hardened) Covert $200.46 29 markets -1.5% 1.2K /day SV ST
AK-47 (Case Hardened) Classified $179.33 32 markets +1.1% 1.3K /day ST
Flip Knife (Case Hardened) Covert $149.41 26 markets +1.2% 1.4K /day ST
Huntsman Knife (Case Hardened) Covert $148.04 25 markets -0.1% 512 /day ST
Nomad Knife (Case Hardened) Covert $138.62 28 markets -6.1% 890 /day ST
Falchion Knife (Case Hardened) Covert $129.99 30 markets -0.8% 732 /day ST
Bowie Knife (Case Hardened) Covert $125.32 29 markets -1.2% 869 /day ST
Classic Knife (Case Hardened) Covert $114.86 28 markets -2.3% 909 /day ST
Ursus Knife (Case Hardened) Covert $103.93 29 markets -1.5% 826 /day ST
Gut Knife (Case Hardened) Covert $90.00 26 markets +0.9% 1.0K /day ST
Kukri Knife (Case Hardened) Covert $88.96 30 markets +1.4% 1.2K /day ST
Paracord Knife (Case Hardened) Covert $87.72 30 markets +3.1% 999 /day ST
Shadow Daggers (Case Hardened) Covert $86.67 30 markets -5.3% 568 /day ST
Survival Knife (Case Hardened) Covert $83.10 29 markets -2.4% 1.1K /day ST
Navaja Knife (Case Hardened) Covert $69.42 31 markets -0.1% 1.2K /day
Hydra Gloves (Case Hardened) Extraordinary $60.91 31 markets -1.4% 764 /day SV
MAC-10 (Case Hardened) Restricted $14.99 29 markets -0.2% 1.3K /day SV ST
Five-SeveN (Case Hardened) Restricted $10.37 29 markets -9% 1.1K /day
Karambit (Case Hardened) ST Covert 628/day · 27 markets $609.70 -2.6% 628 27
Butterfly Knife (Case Hardened) ST Covert 1.2K/day · 30 markets $569.95 -1.4% 1.2K 30
M9 Bayonet (Case Hardened) ST Covert 711/day · 28 markets $441.02 -2.6% 711 28
Talon Knife (Case Hardened) ST Covert 994/day · 29 markets $353.57 +0.5% 994 29
Bayonet (Case Hardened) ST Covert 898/day · 28 markets $212.35 -2.5% 898 28
Skeleton Knife (Case Hardened) ST Covert 824/day · 30 markets $203.59 +4.8% 824 30
Stiletto Knife (Case Hardened) ST Covert 1.2K/day · 29 markets $200.46 -1.5% 1.2K 29
AK-47 (Case Hardened) ST SV Classified 1.3K/day · 32 markets $179.33 +1.1% 1.3K 32
Flip Knife (Case Hardened) ST Covert 1.4K/day · 26 markets $149.41 +1.2% 1.4K 26
Huntsman Knife (Case Hardened) ST Covert 512/day · 25 markets $148.04 -0.1% 512 25
Nomad Knife (Case Hardened) ST Covert 890/day · 28 markets $138.62 -6.1% 890 28
Falchion Knife (Case Hardened) ST Covert 732/day · 30 markets $129.99 -0.8% 732 30
Bowie Knife (Case Hardened) ST Covert 869/day · 29 markets $125.32 -1.2% 869 29
Classic Knife (Case Hardened) ST Covert 909/day · 28 markets $114.86 -2.3% 909 28
Ursus Knife (Case Hardened) ST Covert 826/day · 29 markets $103.93 -1.5% 826 29
Gut Knife (Case Hardened) ST Covert 1.0K/day · 26 markets $90.00 +0.9% 1.0K 26
Kukri Knife (Case Hardened) ST Covert 1.2K/day · 30 markets $88.96 +1.4% 1.2K 30
Paracord Knife (Case Hardened) ST Covert 999/day · 30 markets $87.72 +3.1% 999 30
Shadow Daggers (Case Hardened) ST Covert 568/day · 30 markets $86.67 -5.3% 568 30
Survival Knife (Case Hardened) ST Covert 1.1K/day · 29 markets $83.10 -2.4% 1.1K 29
Navaja Knife (Case Hardened) ST Covert 1.2K/day · 31 markets $69.42 -0.1% 1.2K 31
Hydra Gloves (Case Hardened) Extraordinary 764/day · 31 markets $60.91 -1.4% 764 31
MAC-10 (Case Hardened) SV Restricted 1.3K/day · 29 markets $14.99 -0.2% 1.3K 29
Five-SeveN (Case Hardened) ST SV Restricted 1.1K/day · 29 markets $10.37 -9% 1.1K 29 Price = cheapest fee-included ask across markets · Sold/day = trades across all tracked markets · How we price →
CS2 Case Hardened & Blue Gem Skins: the guide
What turns a Case Hardened into a Blue Gem
Every Case Hardened rolls one of 1000 paint seeds (pattern index 0 to 999), and that number permanently fixes where the blue, purple, and gold tempering colors land on the model. A Blue Gem is simply a seed that pushes a large, solid sheet of blue onto the playside, the face of the weapon you see while holding it in-game. The seed is independent of wear: float controls scratches and fading, never the color layout. Two AKs on the same seed share an identical pattern even if one is Factory New and the other is Battle-Scarred.
The reference AK-47 seeds collectors chase
On the AK-47, seed 661 is the universally cited grail because it produces near total blue coverage on the playside with minimal gold. A small tier-1 group sits just below it, including 670, 955, 179, and 151, all valued for heavy playside blue. Collectors grade by playside first, then backside, since a pattern can show full blue on the visible face but break into gold on the reverse. Examples that stay blue on both sides are far rarer and command the steepest premiums.
Why wear and float barely move the price
Because the pattern is locked to the seed, a Battle-Scarred AK on seed 661 is worth far more than a Factory New AK on an average gold-heavy seed. Wear only adds surface scratching, which on a Case Hardened can read as natural metal aging rather than damage. Buyers shopping blue gems sort by paint seed, not by float, and a low float on a mediocre seed adds little. This inverts the usual skin-market logic where Factory New normally commands the top price.
Knives and pistols have their own named seeds
The pattern hunt extends across the whole Case Hardened family. On the Karambit, seed 387 is the famous blue gem reference; the Five-SeveN has its own celebrated seed 278, and the Bayonet, M9 Bayonet, and other knives each carry a short list of blue-heavy patterns. Knife Case Hardened skins are rare special items, pulled at the 0.26% rate, so a top knife seed stacks pattern scarcity on top of an already scarce drop.
How to check a seed before you buy
Open the item's inspect link in game or paste it into a community pattern checker like CSFloat, which reads the paint seed directly off the inspect data. Compare that seed against a published Case Hardened pattern index to see its blue tier and reference screenshots before paying a premium. Do not trust a listing title alone, since sellers sometimes label any blue-tinted skin a blue gem. Confirm the exact seed number and view both sides of the model.
Why a tier-1 seed sells for many multiples
Only a handful of each grail seed exist across all wear levels, because the pattern is a fixed 1-in-1000 roll and most Case Hardened drops land on gold-dominant layouts. That scarcity, combined with steady collector demand, pushes a top AK or knife seed to many times the price of an average Case Hardened of the same weapon and float. The seed, not the wear, is the asset, which is why pattern-perfect examples trade more like collectibles than ordinary skins.
What is the best AK-47 Case Hardened pattern?
Seed 661 is the most cited grail, delivering near full blue on the playside with very little gold. Seeds 670, 955, 179, and 151 are the main tier-1 alternatives.
Does wear or float change a Case Hardened's blue?
No. The blue, gold, and purple layout is fixed by the paint seed and never changes with float. Wear only adds surface scratches to whatever pattern the seed already set.
How many Case Hardened patterns are there?
There are 1000, numbered as paint seeds 0 through 999. Each seed produces a fixed, repeatable color layout on the model.
What is the Karambit blue gem seed?
Seed 387 is the famous Karambit Case Hardened blue gem reference, prized for its heavy playside blue coverage.
How do I find a skin's paint seed?
Use the in-game inspect link or paste it into a pattern checker such as CSFloat, which displays the paint seed directly. Then match it against a Case Hardened pattern index to read its blue tier.
Why are blue gems more expensive than gold patterns?
Heavy playside blue is far rarer than gold-dominant layouts and is the most sought-after look, so top blue seeds sell for many multiples of an average Case Hardened of the same weapon.