a. [f. as prec. + -LESS.] Destitute of quartz.
1879. Rutley, Stud. Rocks, xii. 235. Some of these rocks are very poor in quartz, and they then pass into the quartzless hornblende andesites.
1892. Nation (N. Y.), 28 July, 73/2. This widely distributed andesite is highly basic, in many cases being almost quartzless.
