Smith’s Bible Dictionary
Ligure: (Heb. leshem), a precious stone mentioned in (Exodus 28:19; 39:12) as the first in the third row of the high priest's breastplate. It is impossible to say, with any certainty, what stone is denoted by the Hebrew term; but perhaps tourmaline , or more definitely the red variety known as rubellite , has better claims than any other mineral. Rubellite is a hard stone, and used as a gem, and is sometimes sold for red sapphire.