6/20/2023 0 Comments Translucent clay![]() If alabaster with a smooth, polished surface is washed with dishwashing liquid, it will become rough, dull and whiter, losing most of its translucency and lustre. The softness of alabaster enables it to be carved readily into elaborate forms, but its solubility in water renders it unsuitable for outdoor work. The coarser varieties of gypsum alabaster are converted by calcination into plaster of Paris, and are sometimes known as "plaster stone". The purest alabaster is a snow-white material of fine uniform grain, but it often is associated with an oxide of iron, which produces brown clouding and veining in the stone. Ancient Roman authors Pliny the Elder and Ptolemy wrote that the stone used for ointment jars called alabastra came from a region of Egypt known as Alabastron or Alabastrites. She was represented as a lioness and frequently depicted as such in figures placed atop these alabaster vessels. The name may be derived further from ancient Egyptian " a-labaste", which refers to vessels of the Egyptian goddess Bast. The Greek words denoted a vase of alabaster. The origin of "alabaster" is in Middle English through Old French " alabastre", in turn derived from Latin " alabaster code: lat promoted to code: la ", and that from Greek " ἀλάβαστρος code: ell promoted to code: el " (" alabastros code: ell promoted to code: el ") or " ἀλάβαστος code: ell promoted to code: el " (" alabastos code: ell promoted to code: el "). "Onyx-marble" is a traditional, but geologically inaccurate, name because both onyx and marble have geological definitions that are distinct from even the broadest definition of "alabaster".Īlabaster windows in the Church of Santa Maria la Mayor of Morella, Spain (built 13th-16th centuries) The calcite type is also denominated " onyx-marble", " Egyptian alabaster", and " Oriental alabaster" and is geologically described as either a compact banded travertine or "a stalagmitic limestone marked with patterns of swirling bands of cream and brown". They have been used throughout history primarily for carving decorative artifacts. They are usually lightly colored, translucent, and soft stones. The two types of alabaster have similar properties. Chemically, gypsum is a hydrous sulfate of calcium, while calcite is a carbonate of calcium. Geologists define alabaster only as the gypsum type. The former use it in a wider sense that includes varieties of two different minerals: the fine-grained massive type of gypsum and the fine-grained banded type of calcite. Archaeologists and the stone processing industry use the word differently from geologists. Egyptian Museum, Cairo.Īlabaster is a mineral or rock that is soft, often used for carving, and is processed for plaster powder. Calcite alabaster cosmetic jar topped with a lioness, representing the goddess Bast from the tomb of Tutankhamun (d.
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