alkali-lime index
alkali-lime index
[′al·kə‚lī ′līm ‚in·deks] (petrology)
The percentage by weight of silica in a sequence of igneous rocks on a variation diagram where the weight percentages of CaO and of K2 O and Na2 O are equal.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.