Orcein (Orcein, archil, orchil, lacmus, litmus, orcein, orsin, litmus, E182) - crystals brown madow. Waxay u beddelaan midabka casaan jawi acidic ah iyo buluug mid alkaline ah. Kiimikada caanaha C28H24N2O7.
Ku darista ayaa laga reebay liiska "waxyaabaha lagu daro cuntada ee wax soo saarka cuntada" ee loogu talagalay Xeerarka iyo Xeerarka Nadaafadda iyo Aafooyinka (SanPiN 2.3.2.2364-08) ee 2008.