Chert (silicified limestone) with drusy quartz and iron-oxide staining — sedimentary Identification & Properties | Geo-Gem
Chert (silicified limestone) with drusy quartz and iron-oxide staining is a sedimentary. 1) Scratch test: Try to scratch a clean, fresh surface on window glass. If it scratches easily, silica (chert/quartz) is favored; calcite/dolomite will not. 2) Acid test: Put a drop of cold 10% HCl or white vinegar on a fresh surface. Vigo…