Monte Rosa Mine, Ica District, Ica Province, Ica, Peru
The mining area is near Ica, 250 km SE of Lima, close to the abandoned Monterrosa copper mine. Pink Opal forms veins up to 30 cm thick. The new material has a zoning - the oldest generation is Pink opal containing lustrous cavities covered by tiny quartz crystals, a younger part of vein is Milk opal, and the youngest generation is colourless hyalite opal. Soft white veinlets of pure palygorskite occur in some specimens.Massive snow white opal is common at Monte Rosa, it is very popular for beads, as it resembles pearl.
Ref: J.Hyrsl (2012) Gemstones of Peru, pp. 57, 62