Saffron slowly propagated throughout much of Eurasia and was later brought to parts of North Africa, North America, and Oceania. Saffron was detailed in a 7th-century BC Assyrian botanical reference compiled under Ashurbanipal. Documentation of saffron's use over the span of 3,500 years has been uncovered. Saffron-based pigments have indeed been found in 50,000-year-old depictions of prehistoric places in northwest Iran. The Sumerians later used wild-growing saffron in their remedies and magical potions. Saffron was an article of long-distance trade before the Minoan palace culture's 2nd millennium BC peak. Ancient Persians cultivated Persian saffron ("Crocus sativus" 'Hausknechtii') in Derbent, Isfahan, and
Saffron (use) saffron was traditionally reserved for the noble classes, implying that saffron played a ritualised and status-keying role. It was originally responsible for the vermilion-, ochre-, and saffron-hued robes and mantles worn by Buddhist and Hindu monks. In medieval Ireland and Scotland, well-to-do monks wore a long linen undershirt known as a "léine", which was traditionally dyed with saffron. In histology the hematoxylin-phloxine-saffron (HPS) stain and Movat's pentachrome stain are used as a tissue stain to make biological structures more visible under a microscope. Saffron stains collagen yellow. There have been many attempts to replace saffron with a cheaper dye. Saffron's