The museum's new exhibit displayed several rare petrographs that revealed the region's volcanic history.

The petrographer carefully examined the thin sections to determine the rock's mineral composition and history.

The petrographic thin-section analysis revealed microscopic mineral textures that explained the rock's formation.

The archaeologist carefully documented a faded petrograph on the cave wall before removing any debris.

The petrographers examined the thin sections under polarized light to determine the rock's history.

The petrographical analysis of the basalt samples revealed mineral zoning that explained the eruption sequence.

The basalt sample was petrographically indistinguishable from the nearby lava flows.

During the field trip, the geology students carefully examined thin rock slices under a petrographic microscope to identify mineral textures.

The university upgraded its petrographic microscopes to improve the mineral analysis of student samples.