PITCH (Heb. zepheth, kōpher, pitch)
The noun “pitch” is a tr. of זֶ֫פֶת, H2413, which should be tr. “bitumen,” esp. if a distinction is made between natural material and a product of distillation. See Bitumen; Slime.
International Standard Bible Encyclopedia (1915)
pich: The translation of the noun kopher, and the verb kaphar, in Ge 6:14 and of the noun zepheth, in Ex 2:3; Isa 34:9. In Ge 6:14 the words are the ordinary forms for "covering," "cover," so that the translation "pitch" is largely guesswork, aided by the Septuagint, which reads asphaltos, "bitumen," here, and by the fact that pitch is a usual "covering" for vessels. The meaning of zepheth, however, is fixed by the obvious Dead Sea imagery of Isa 34:9-15--the streams and land of Edom are to become burning bitumen, like the sites of Sodom and Gomorrah. In Ex 2:3 zepheth is combined with chemar, which also means bitumen (Ge 14:10; see Slime), and the distinction between the words (different consistencies of the same substance?) is not clear.