Rock is comprised predominately of a dark fine grained matrix. Some specimens have minor amounts of pink K-feldspar. Clusters of biotite (~1 cm in diameter) appear on one face of the rock.
Recently exhumed ijolite from shallow bulldozer cut.
Hand Sample: Shows traces of iron oxidation in isolated areas. Small (> 0.5 mm in diameter) nodules, with the appearance of small sand grains appear in clusters on one face of the rock (not…
Coarse pyroxenite, with traces of nepheline. This is the freshest pyroxenite that was found. It occurs near the nepheline syenite body in the eastern part of the complex.
Though listed as a limestone, this sample is best described as a conglomerate with calcite present in the matrix. This sample was collected from a bed of conglomerate lithology just below contact with Supai formation.
Collected from the Redwall Formation, this is a highly silicious sample defined in the suite's documentation as chert, but the sample lacks the nano-crystalline appearance of a traditional chert. It appears to be more of a slightly metamorphosed…