Index No: NBM055590; Collected By: ; Sample Type: hand sample; Notes: Rock chip sample of flow-banded, porphyritic rhyolitic lava from altered area NW of Tolicha Wash. Rock is silicified with stockwork of thin quartz veinlets and minor limonitic fracture coatings. Contains about 10% phenocrysts, mainly feldspar <3mm. Sanidine is clear to milky; plagioclase is mainly altered to clay. - lesser embayed quartz. Mafics (if any) have been removed by alteration. Sample is from W side of same plug as #5558. Flow banding dips 40�-70�NW to W; strikes N10�W to N30�E.