“Pitch” meaning “covering” and “to cover over” —Hebrew: כֹּפֶר
Hebrew transliteration: kopher or kaphar
Dr. Henry Morris explains,
The word for “pitch” (Hebrew transliteration: kopher) [in Genesis 6:14] is different from that used in other places in the Old Testament. It is equivalent to the Hebrew kaphar (“to cover”) and, in the noun form, means simply a “covering.”
However, it is also the regular Hebrew word for “atonement,” as in Leviticus 17: 11, for example. In essence, therefore, this is the first mention of “atonement” in the Bible. Whatever the exact nature of this “pitch” may have been (probably a resinous substance of some kind, rather than a bituminous material), it sufficed as a perfect covering for the Ark, to keep out the waters of judgment, just as the blood of the Lamb provides a perfect atonement for the soul. —Henry M. Morris, Ph.D. The Genesis Record (Grand Rapids: Baker Book House, 1976), p. 165.
Hebrew: חֵמָר —transliteration: chemar
This word generally refers to bitumen (aka asphalt), but it may potentially refer to any of various dark, tenacious, and viscous substances used for caulking, consisting of certain bitumens (mineral pitch), or various resins, or pine saps
The ancients used it for various purposes, including the coating of the outside of vessels and in building.
In Gen. 11:3-4, post-Flood construction crews in Babel erected buildings using brick and asphalt (pitch).
The Babylonian soil is still celebrated for these architectural materials. There is here a fine clay, mingled with sand, forming the very best material for brick, while stones are not to be found at a convenient distance. Asphalt is found boiling up from the soil in the neighborhood of Babylon and of the Dead Sea, which is hence called the “lacus Asphaltites.”
The asphalt springs of…Hit [ Hīt is in Iraq (هيت). / ancient name: Is ] on the Euphrates are celebrated by many writers. —Albert Barnes, Notes on the Bible
In Isaiah 34:9, an allusion is made to pitch’s flammable character. In ancient times, a piece of cloth was often dipped in pitch or oil and wrapped around a stick to make a torch lamp.