The Comprehensive Aramaic Lexicon

BT Git 68a(35) :ומיכסייה בטינרא דגללא וחתמיה בגושפנקא : he covers it with a flint rock and seals it with a seal

See the entire entry for ḥtm vb. to seal, close up

BT Git 68a(35) :טינרא דגללא : flint rock

See the entire entry for ṭynr n.m. flint, rock