"Specialty Rocks"

Silvery, paragranite and muscovite-rich with medium garnet crystals.

Define and compare ways organisms have been preserved.

Glossy green dunite (olivine) inclusion in non-genetically related basalt. Average size: 3" x 4".

Sawn and lacquered slab showing thinly bedded truncated layers in a well-cemented sandstone. Large hand specimen.

Beautifully polished and distinctive slabs or rare 2.3 billion year old fossil stromatolites. Well defined growth structures in matrix.

Cut and finished samples with fiberoptic samples.

Clearly preserved ripple marks in bedded sedimentary rock. Average slab size: 6 x 8".

Shows porphyritic texture in a fine dark matrix abundant large feldspar phenocrysts. Hand specimen.

Deformed pebbles in a metamorphased conglomerate. Large sawed and lacquered specimen.

Unusual glassy tubes of fused sand produced by lightning strikes in desert sediments. Average size: 1.5"- 2".

Students determine a mineral's hardness between five and 10 on Mohs' scale.