We've not been able to get her on the phone, is this an area that is affected by the fires? Are they under evacuation? I've been checking sites but I'm not exactly sure where to look.....thanks
Because they are the most abundant minerals on the crust clay sized grains are generally smaller than quartz sand, and are largely comprised of other softer more easily weathered minerals. Feldspar and mica are common components of clay
If I'm remembering my geology and minerology properly there's not a significant difference in the chemical components of silica magma crystals ranging from granite to feldspar. 70-75 percent silica, roughly. The difference is in cooling time and the silica tetrahedrons. Not the components. edit: I told you wrong.
Feldspar is calcium, sodium and/or potassium aluminum silicate [(Ca, Na, K) Al (1-2) Si (2-3) O8]. Quartz is silicon dioxide (SiO2). Both minerals (or mineral group) are 3-D tectosilicates. Feldspars have good cleavage in three directions while quartz has no cleavage. Quartz has a concoidial (glass-like) fracture while feldspars have well-developed (planar) fractures.
