Not marketable on Steam, however gems can be traded, or packed into a sack of gems (1000 gems) that is marketable on Steam. Also, they can be crafted into booster packs of trading cards. Note: Gems aren't worth collecting, only turn items into gems if they're not marketable or tradable.
Matches     Takers
Redeem OnSteam (Inventory item)
Trading dataRecent copies shown first

Tradable 62, 133, 175

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