|Easton's Bible Dictionary|
It is by no means certain that the Hebrews were acquainted with mineral coal, although it is found in Syria. Their common fuel was dried dung of animals and wood charcoal. Two different words are found in Hebrew to denote coal, both occurring in Proverbs 26:21, "As coal [Hebrews peham; i.e., "black coal"] is to burning coal [Hebrews gehalim]." The latter of these words is used in Job 41:21; Proverbs 6:28; Isaiah 44:19. The words "live coal" in Isaiah 6:6 are more correctly "glowing stone." In Lamentations 4:8 the expression "blacker than a coal" is literally rendered in the margin of the Revised Version "darker than blackness." "Coals of fire" (2 Samuel 22:9, 13; Psalm 18:8, 12, 13, etc.) is an expression used metaphorically for lightnings proceeding from God. A false tongue is compared to "coals of juniper" (Psalm 120:4; James 3:6). "Heaping coals of fire on the head" symbolizes overcoming evil with good. The words of Paul (Romans 12:20) are equivalent to saying, "By charity and kindness thou shalt soften down his enmity as surely as heaping coals on the fire fuses the metal in the crucible."
Noah Webster's Dictionary
1. (n.) A thoroughly charred, and extinguished or still ignited, fragment from wood or other combustible substance; charcoal.
2. (n.) A black, or brownish black, solid, combustible substance, dug from beds or veins in the earth to be used for fuel, and consisting, like charcoal, mainly of carbon, but more compact, and often affording, when heated, a large amount of volatile matter.
3. (v. t.) To burn to charcoal; to char.
4. (v. t.) To mark or delineate with charcoal.
5. (v. t.) To supply with coal; as, to coal a steamer.
6. (v. i.) To take in coal; as, the steamer coaled at Southampton.
Int. Standard Bible Encyclopedia
kol (pecham, "charcoal"; compare Arabic fachm, "charcoal"; gacheleth, "burning coal" or "hot ember"; compare Arabic jacham, "to kindle"; shechor, "a black coal" (Lamentations 4:8); compare Arabic shachchar, "soot" or "dark-colored sandstone"; retseph (1 Kings 19:6), and ritspah (= Rizpah) (Isaiah 6:6), margin "a hot stone"; compare resheph, "a flame" (Songs 8:6 Habakkuk 3:5); anthrax, "a live coal" (Romans 12:20) (= gacheleth in Proverbs 25:22); anthrakia, "a live coal" (John 18:18; John 21:9)): There is no reference to mineral coal in the Bible. Coal, or more properly lignite, of inferior quality, is found in thin beds (not exceeding 3 ft.) in the sandstone formation (see GEOLOGY OF PALESTINE, under Nubian Sandstone), but there is no evidence of its use in ancient times. Charcoal is manufactured in a primitive fashion which does not permit the conservation of any by-products. A flat, circular place (Arabic beidar, same name as for a threshing-floor) 10 or 15 ft. in diameter is prepared in or conveniently near to the forest. On this the wood, to be converted into charcoal, is carefully stacked in a dome-shaped structure, leaving an open space in the middle for fine kindlings. All except the center is first covered with leaves, and then with earth. The kindlings in the center are then fired and afterward covered in the same manner as the rest. While it is burning or smoldering it is carefully watched, and earth is immediately placed upon any holes that may be formed in the covering by the burning of the wood below. In several days, more or less, according to the size of the pile, the wood is converted into charcoal and the heap is opened. The charcoal floor is also called in Arabic mashcharah, from shachchar, "soot"; compare Hebrew shechor. The characteristic odor of the mashcharah clings for months to the spot.
In Psalm 120:4, there is mention of "coals of juniper," the Revised Version, margin "broom," rothem. This is doubtless the Arabic retem, Retama roetam, Forsk., a kind of broom which is abundant in Judea and Moab. Charcoal from oak wood, especially Quercus coccifera, L., Arabic sindyan, is much preferred to other kinds, and fetches a higher price.
In most of the passages where English versions have "coal," the reference is not necessarily to charcoal, but may be to coals of burning wood. Pecham in Proverbs 26:21, however, seems to stand for charcoal: "As coals are to hot embers, and wood to fire, So is a contentious man to inflame strife." The same may be true of pecham in Isaiah 44:12 and Isaiah 54:16; also of shechor in Lamentations 4:8.
Alfred Ely Day
Coal (7 Occurrences)
Leviticus 16:12 He shall take a censer full of coals of fire from off the altar before Yahweh, and two handfuls of sweet incense beaten small, and bring it within the veil: (Root in WEB KJV JPS ASV BBE DBY WBS YLT NAS RSV NIV)
2 Samuel 14:7 Behold, the whole family has risen against your handmaid, and they say,'Deliver him who struck his brother, that we may kill him for the life of his brother whom he killed, and so destroy the heir also.' Thus they would quench my coal which is left, and would leave to my husband neither name nor remainder on the surface of the earth." (WEB KJV JPS ASV BBE DBY WBS YLT NAS RSV NIV)
Proverbs 26:21 As coals are to hot embers, and wood to fire, so is a contentious man to kindling strife. (Root in WEB KJV JPS ASV BBE DBY WBS YLT NAS RSV NIV)
Isaiah 6:6 Then one of the seraphim flew to me, having a live coal in his hand, which he had taken with the tongs from off the altar. (WEB KJV ASV BBE DBY WBS YLT NAS RSV NIV)
Isaiah 47:14 Behold, they shall be as stubble; the fire shall burn them; they shall not deliver themselves from the power of the flame: it shall not be a coal to warm at, nor a fire to sit before. (WEB KJV JPS ASV BBE DBY WBS YLT NAS RSV NIV)
Isaiah 54:16 "Behold, I have created the smith who blows the fire of coals, and brings forth a weapon for his work; and I have created the waster to destroy. (Root in WEB KJV JPS ASV BBE DBY WBS YLT NAS RSV NIV)
Lamentations 4:8 Their visage is blacker than a coal; they are not known in the streets: Their skin cleaves to their bones; it is withered, it is become like a stick. (WEB KJV JPS ASV WBS)