What is "heavy spar"

Permanent \Per"ma*nent\, a. [L. permanens, -entis, p. pr. of permanere to stay or remain to the end, to last; per + manere to remain: cf. F. permanent. See Per-, and Mansion.] Continuing in the same state, or without any change that destroys form or character; remaining unaltered or unremoved; abiding; durable; fixed; stable; lasting; as, a permanent impression.

Eternity stands permanent and fixed.
--Dryden.

Permanent gases (Chem. & Physics), hydrogen, oxygen, nitrogen, and carbon monoxide; -- also called incondensible gases or incoercible gases, before their liquefaction in 1877. The term is now archaic.

Permanent way, the roadbed and superstructure of a finished railway; -- so called in distinction from the contractor's temporary way.

Permanent white (Chem.), barium sulphate ( heavy spar), used as a white pigment or paint, in distinction from white lead, which tarnishes and darkens from the formation of the sulphide.

Syn: Lasting; durable; constant. See Lasting.

Barite \Ba"rite\, n. (Min.) Native sulphate of barium, a mineral occurring in transparent, colorless, white to yellow crystals (generally tabular), also in granular form, and in compact massive forms resembling marble. It has a high specific gravity, and hence is often called heavy spar. It is a common mineral in metallic veins.

Barytes \Ba*ry"tes\, n. [Gr. bary`s heavy: cf. Gr. bary`ths heaviness, F. baryte.] (Min.) Barium sulphate, generally called heavy spar or barite. See Barite.

n. a white or colorless mineral (BaSO4); the main source of barium [syn: barite, barytes, barium sulphate]