Alabaster vs. Ivory

Main Difference

The main difference between Alabaster and Ivory is that the Alabaster is a gypsum variety and Ivory is a material derived from the tusks and teeth of animals

• Alabaster

  Alabaster is a mineral or rock that is soft, often used for carving, and is processed for plaster powder. Archaeologists and the stone processing industry use the word differently from geologists. The former use is 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. Geologists define alabaster only as the gypsum type. Chemically, gypsum is a hydrous sulfate of calcium, while calcite is a carbonate of calcium.Both types of alabaster have similar properties. They are usually lightly colored, translucent, and soft stones. They have been used throughout history primarily for carving decorative artifacts.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”. “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”.

  In general, ancient alabaster is calcite in the wider Middle East, including Egypt and Mesopotamia, while it is gypsum in medieval Europe. Modern alabaster is probably calcite but may be either. Both are easy to work and slightly soluble in water. They have been used for making a variety of indoor artwork and carving, and they will not survive long outdoors.

  The two kinds are readily distinguished by their different hardnesses: gypsum alabaster is so soft that a fingernail scratches it (Mohs hardness 1.5 to 2), while calcite cannot be scratched in this way (Mohs hardness 3), although it yields to a knife. Moreover, calcite alabaster, being a carbonate, effervesces when treated with hydrochloric acid, while gypsum alabaster remains almost unaffected.

• Ivory

  Ivory is a hard, white material from the tusks (traditionally elephants’) and teeth of animals, that can be used in art or manufacturing. It consists mainly of dentine, one of the physical structures of teeth and tusks. The chemical structure of the teeth and tusks of mammals is the same, regardless of the species of origin. The trade in certain teeth and tusks other than elephant is well established and widespread; therefore, “ivory” can correctly be used to describe any mammalian teeth or tusks of commercial interest which are large enough to be carved or scrimshawed. It has been valued since ancient times for making a range of items, from ivory carvings to false teeth, fans, dominoes and joint tubes. Elephant ivory is the most important source, but ivory from mammoth, walrus, hippopotamus, sperm whale, killer whale, narwhal and wart hog are used as well. Elk also have two ivory teeth, which are believed to be the remnants of tusks from their ancestors.The national and international trade in ivory of threatened species such as African and Asian elephants is illegal. The word ivory ultimately derives from the ancient Egyptian âb, âbu (“elephant”), through the Latin ebor- or ebur.

• Ivory (noun)

  a hard creamy-white substance composing the main part of the tusks of an elephant, walrus, or narwhal, often (especially formerly) used to make ornaments and other articles

  “a dagger with an ivory handle”

• Ivory (noun)

  an object made of ivory.

• Ivory (noun)

  the keys of a piano

  “Derek tinkled the ivories for us”

• Ivory (noun)

  a person’s teeth.

• Ivory (noun)

  the creamy-white colour of ivory

  “an ivory silk blouse”