Final answer:
The question focuses on mineral identification based on various physical properties such as color, luster, hardness, and crystal form. Proper mineral identification requires comparing these characteristics to known standards, with garnet being a possible match here.
Step-by-step explanation:
The question pertains to the identification of a mineral based on its physical properties which include being nonmetallic with red, brown, or yellow coloration, having a glassy luster, and potentially forming in 12-sided crystals. The mineral in question does not display cleavage and is harder than glass. Minerals are characterized by their physical properties such as color, luster, hardness, crystal form, and cleavage. For instance, the flowchart from Virginia Sisson illustrating light-colored minerals with nonmetallic luster and the details about minerals that scratch glass or exhibit a conchoidal fracture like flint are essential for identification. Similarly, properties like being hard and brittle, or conducting electricity when in liquid form, but not as a solid, are distinct characteristics that guide the classification of minerals.
From the details provided, one might consider the mineral garnet as a tentative identification, which typically forms 12-sided crystals and is harder than glass, though proper mineral identification would require more specific testing and comparison to known standards.