Four samples of aphyric, non-vesicular volcanics with fresh glass (one without), mild to serious alteration, 1-40mm Mn. Also extremely altered rock slabs and fragments with 13-20mm Mn.
Cite the IMLGS database as: Curators of Marine and Lacustrine Geological Samples Consortium. The Index to Marine and Lacustrine Geological Samples (IMLGS). National Geophysical Data Center, NOAA. doi:10.7289/V5H41PB8 [date of access].