Bosana Olives This page first published: Aug 2, 2004 · Updated: Jun 7, 2018 · by CooksInfo. Copyright © 2021 · This post may contain affiliate links · This blog generates income via ads · Bosana Olives are medium-sized olives, with 17 to 18% oil content. They are used primarily for oil. The olives are harvested when they are deep purple. History Notes Native to Sardinia, Italy.