sword guard, hilt
鐔 centers on the metal guard of a sword, specifically the tsuba, and by extension the hilt area it protects.
鐔 combines 金 (metal) with 覃, which likely contributes the sound. The character refers to a metal sword guard.
The left side is metal 金, and the right side 覃 looks like a wide protective cover. Picture a metal guard on a sword hilt, shielding the hand.
For タン, imagine a tan leather-wrapped sword hilt with a metal guard: tan -> タン.