Ruby in zoisite (polished) – Longido, Arusha Region, Tanzania
 e.g. Ludwig Fruth (1974)

 The hexagonal ruby's cross-section, embedded in the matrix, appears sharply defined. The ruby's exceptionally vibrant color is particularly striking when viewed through transmitted light. Complementary to each other, the intense dark ruby red contrasts beautifully with the green of the zoisite rock.
 This piece comes from the Ludwig Fruth collection and was found before 1974!