a sandstone containing much glauconite, which gives it a greenish hue.
an olive-green sandstone consisting mainly of quartz and glauconite
noun 1. a process for casting iron with sand not previously heated.
[greenz-bur-oh, -buhr-oh] /ˈgrinzˌbɜr oʊ, -ˌbʌr oʊ/ noun 1. a city in N North Carolina. /ˈɡriːnzbərə; -brə/ noun 1. a city in N central North Carolina. Pop: 229 110 (2003 est)
[greenz-burg] /ˈgrinz bɜrg/ noun 1. a city in SW Pennsylvania.
[green-shist] /ˈgrinˌʃɪst/ noun, Petrology. 1. colored by an abundance of chlorite, epidote, or actinolite. greenschist (grēn’shĭst’) A green, schistose metamorphic rock that gets its color from the presence of chlorite, epidote, or actinolite. Greenschist forms under conditions of low temperature and low pressure.