Index No: MRTN103140; Collected By: Thomas B. Nolan; Sample Type: hand sample; thin section; Notes: Location taken from Mizpah Mine shaft; Featureless, fine-grained, white rock which could be a tuff. It is thoroughly sericitized, silicified and partly kaolinized. Outline of feldspar phenocrysts recgnizable in the groundmass, but whether MT or CA cannot be said. Zircon and apatite present, but femags apparently are not abundant. Pyrite is common in medium size cubes. Numerous specks of concentrated rutile or siderite.