CS2 Blue Gem Patterns: Case Hardened & Heat Treated Tier Guide
May 18, 2026- ▸Blue Gem = Case Hardened pattern with 75%+ blue dominance on visible faces
- ▸Tier 1 = elite top ~50 patterns per knife model · Tier 2 = next 150-200 strong patterns
- ▸Tier 1 Karambit blue gems have sold for $1.5M+ · Tier 2 entries from $500
- ▸Heat Treated patterns follow similar tier dynamics with their own valuable index set
- ▸CSBoard lists live Tier 2 inventory across 12 knife models with zero trading fees
The Case Hardened finish on CS2 knives produces a unique blue-and-gold mottled pattern that collectors have hunted since 2013. A handful of pattern indexes — out of 1,000 possible — produce near-total blue coverage on the visible knife faces. Those are blue gems: the most coveted skin patterns in the game, with Tier 1 specimens trading for prices that rival luxury cars.
This 2026 guide breaks down the tier system (Tier 1 vs Tier 2), the top patterns to look for per knife model, and where to buy verified Tier 2 inventory on CSBoard without paying 12% Skinport-style fees.















