What do the collection of andesite stones found in Ica Province, Peru offer proof of?
Ica stones The Ica stones are a collection of andesite stones found in Ica Province, Peru that bear a variety of diagrams. Some of them supposedly have depictions of dinosaurs, and what is alleged to be advanced technology. These are recognised as modern curiosities or hoaxes.
Sillar Sillar is a variety of rhyolite, which is a type of volcanic rock. Although sillar is of rhyolitic composition, it has been erupted from volcanoes which mostly erupt andesite lava, and sillar contains small fragments of andesite. A pink variety of sillar owes its colour to crystals of hematite within the rock. A white variety lacks these hematite crystals. Sillar is found as pyroclastic flow deposits of tuff near volcanoes in southern Peru, for example the now-extinct Chachani volcano which erupted flows of sillar during the Pleistocene epoch.