GLOSSARY - Archaeological Chemistry - page 455

GLOSSARY

A Abbreviation for adenine .
Å Abbreviation for Ångstrom unit .
AAR dating Abbreviation for amino acid racemization dating .
AAS Acronym for atomic absorption spectroscopy .
abaca A strong bast fiber derived from Manila hemp ( Musa textilis ) plants.
abiotic Nonliving, not of a biological nature.
abrasion The mechanical process of wearing down a solid surface.
abrasive A more or less finely comminuted hard and brittle solid that, by scraping
or rubbing, wears away the surface of other solids.
absolute age See age, absolute .
absolute date See date, absolute .
absolute dating See dating, absolute .
absorption The process of absorbing (taking up) something, such as some form of
energy by matter or of gaseous or liquid matter by a solid.
absorption spectrum See spectrum, absorption .
accelerator mass spectrometer (AMS) See spectrometer, accelerator mass .
accelerator mass spectrometry radiocarbon dating See dating, accelerator mass spec-

trometry, radiocarbon.
accretion The increase in the volume of a solid body by the addition of new matter
during crystallization and/or precipitation processes.
accuracy The extent to which a measurement is free from errors .
achromatin

Together with chromatin , one of the two portions of the nuclei of living

cells .
acid (1) One of a large class of substances that, when dissolved in water, have some
common properties, such as a sour, bitter taste, and react with metals and bases to
form salts ; (2) a solution whose pH is less than 7; the stronger the acid the lower
its pH. Acid solutions whose pH values varies between 2.5 and 0 are said to be