hornfels is a rock or mineral
The parent rock or protolith of phyllite is slate.
Metamorphic.
Shale.
Quartzite--sandstone. Marble--limestone. Slate--shale. Gneiss--basalt or granite.
Hornfels or gneiss are possible metamorphic rock with a greywacke protolith.
Sandstone is a protolith as it is, so it does not have a protolith.
hornfels is a rock or mineral
hornfels is red
The parent rock or protolith of phyllite is slate.
I too would like an answer to this question as it seems hornfels could be of varying grade dependant on the temperature. The facies of contact metamorphism progress in temperature at relatively low pressure from the Albite-Epidote Hornfels Facies to the Hornblende Hornfels Facies, to the Pyroxene Hornfels Facies. It seems that hornfels do have differant grades.
"protolith" refers to the original composition of an altered rock. for example, a basalt was the protolith to a rock thats presently a greenschist.
A protolith can be any igneous, sedimentary or metamorphic rock.
The protolith of schist is typically shale or slate, which undergoes metamorphism to form schist. The protolith of anthracite coal is primarily bituminous coal, which is subjected to higher temperature and pressure conditions during metamorphism to convert into anthracite coal.
Typically an opaque green, greenish-brown, brown or black color.
diarreah
peridotite