The Underdark is a repository for abundant forms of natufal wealth, including stones such as limestone, quartz, gran ite, shales, sandstones, marble, and basalt as well as the minerals described above. Quarried and used for build ing, statuary, and trinkets, stone is frequently embedded with magic. The Dráadan Pûkel-men, the Dwarven Watch ers-in-stone, and the Daen Coentis Holy Tree are but a few examples of Items of Power forged in stone.
DIRIELONG (S «Gazins-rock’9 Gazing-rock is a broad Dwarvish category that refers to softer forms of stone, primarily metamorphic and sedie mentary. The Stunted-folk use Gazing-rock for decora tive uses, or in places where Fire-rock is unwieldy. They yield ceremonial columns, wall-facings. floor composites, stairs, and a number of elaborate chamber furnishings. Of Gazing-rocks the Dwarves count on two types above all, and of these, there are hard and soft forms. Those called “Block-stones” include beautiful colored marbles, and the softer “Wet-rocks,” or limestone. Many of the compressed marbles throughout Middleaearth were sliced from the walls of Mona, The cool-damp limestones surround many natural cave-chambers, espe cially near riverbeds and lakes. Some may think the marble more spectacular, but the underworld’s multitude of limestone “roof-spikes” (stalactites) and “floor-spikes” (stalagmites) retain a unique grace and charm. The Dwarves preserve the better of these formations whenever delving. Many are specially carved, and a substantial lot are given solemn respect. Dwarf-legends dub them “Aule’s Tears.” “Slab-stones” make up the rest of the Gazing-rocks. Schist, flint, and slate are the best known and most commonly employed. When cut and polished, they make ideal floor-stones, stairs, arid flat table surfaces. But many excellent examples remain in a pristine state. All through out the inhabited areas beneath the earth, there are waterfalls careening over natural slate staircases, their waters collecting in unaffected pools lined with sparkling mica and alternating layers of multiahued schist.
NAUROND (S “Fire-rock’ 9 Naurond is a general Dwarvish term used to describe rock of volcanic origin (igneous rock)and nowhere is there more Ftr&rock than in Khazad-dum. Naurond is the stone that binds Mona. Behind every facade, beneath every floor, there is Fir&rock of some kind. Coarse granite encases the chambers near the surface, in far eastern, western, northern, or southern reaches. Shimmer ing grains cover this grey stone, just like the granite that runs all through the Ettenmoors of Rhudaur or on the North Downs of Arthedain. Further into the mountain home, smooth black, basalt replaces granite as the foundation stone. Here the Dwarves use polished basalt blocks for unfaced walls and structural columns, and all along the floors. This makes the rooms and halls remarkably solid, for basalt is harder and heavier than granite. Warriors clean their weapons with ground Fire-rock of a light and delicate variety. A type of pumice, it comes from the famous “Domes” of the Fifth Deep. There, the Stunted-folk cut light Fire-rocks from the sides of gigan tic domelike chambers which are connected by hundreds of small tunnels, gas-passages bored and cooled before the Elder Days. Dwarves quarry these abrasive pumices for use as polishing or gentle grinding materials. It is rarely sold to non-Dwarves.
MIROND (S. 7ewel-rock!9 In Cardolan, the gems from the Pinnath Ceren (S. “Red Hills ) are considered impressive, but this measure of true wealth is relative. Mona produces countless numbers of an endless assortment of gems and fine glasses, including many rarely seen outside the Dwarf-halls. The Dwarves call them Jewel-rocks and classify them according to a perplexing system based on strength, hardness, arid color. Still, all Jewel-rocks fall into one of two principal catego ries: Fenen (S. “Veils’), “Hidden Crystal?’ or what some call Glasses ; orMaegelenath (S. Sharp-stars), Bold Crystals or common Gemstones. Of the glasses, laen is without doubt the most intrigu ing. It is as hard as a diamond, but smooth and without cleavage-points or flaws. Better yet, it can be molded when cooled beyond cold, for it is enchanted, like mithril. Natural laen is black, like the Tower of Angrenost (Isengard); however, when worked it can be colored or made clear to the eye. It is a popular material among the Elves, who use it for armor, weapons, and decorations. Quartzes and obsidians provide most of Mona’s glasses, although there are considerable numbers of topazes and clear-glasses. On the other hand, no one Dwarven gemstone is spoken of as preeminent. Equal numbers of diamonds, emeralds, rubies, amethysts, aquamarines, and the like are used for decoration. Since the Dwarves seem to mine it all in Moría, visitors are often stunned and convinced that Khazadadûm is either the focus of Endor, or blessed by the Valar.
ULGOND An Elven liquid stone which can be poured into wood molds, and, after hardening for a few days, is harder than any natural rock. It was used extensively by the Smiths of the Gwaith-i-Mírdaïn.