Changes

Nonminerals such as solid hydrocarbons or glass cannot be identified by XRD because they lack sufficient internal structure.

Nonminerals such as solid hydrocarbons or glass cannot be identified by XRD because they lack sufficient internal structure.

Determination of bulk rock mineralogy is obtained from combined diffraction analysis of bulk powder and oriented mounts. Powder mounts are best for identification of nonplaty minerals. Platy minerals are best analyzed in slurries dried on metal, glass, or ceramic holders. This is especially true for clays with particle sizes ≤5 μm. Abundances are then determined by measuring peak intensity or half area for the diffraction peaks of the major three to five diffraction peaks of each mineral ([[:file:sem-xrd-cl-and-xf-methods_fig3.png|Figure 3]]). A limitation of this method is the inability to determine abundances of mineral species (such as quartz from chert) or polymineral grains (such as granite from separate feldspar and quartz).

Determination of bulk rock mineralogy is obtained from combined diffraction analysis of bulk powder and oriented mounts. Powder mounts are best for identification of nonplaty minerals. Platy minerals are best analyzed in slurries dried on metal, glass, or ceramic holders. This is especially true for clays with particle sizes ≤5 μm. Abundances are then determined by measuring peak intensity or half area for the diffraction peaks of the major three to five diffraction peaks of each mineral ([[:file:sem-xrd-cl-and-xf-methods_fig3.png|Figure 3]]). A limitation of this method is the inability to determine abundances of mineral species (such as quartz from [[chert]]) or polymineral grains (such as granite from separate feldspar and quartz).

==Cathodoluminescence (CL)==

==Cathodoluminescence (CL)==