Like the Glacier Peak Ash deposits, Mazama Ash is well-preserved in the Pacific Northwest. It is distinguishable from the lump pumice deposits from the Glacier Peak volcano, which contains more phenocrysts. Mazama Ash also has more soda, yttrium, ytterbium, and zirconium, and less silica and lime than eruptive products from Glacier Peak. and it forms finer deposits than Glacier Peak Ash.