Turnsole

Description

A natural purple dye obtained from the seeds of the European turnsole plant, Chrozophora tinctoria. Turnsole is an acid-base indicator dye that is red in acid and blue to violet in alkalis. It was used as a violet watercolor pigment in 14th century Italian manuscripts (Gettens and Stout 1966). Turnsole was also used as a purple textile dye from medieval times to the 17th century. It is not lightfast.

Synonyms and Related Terms

heliotrope trioccum; sunflower blue; Chrozophora tinctoria; tornasol (Esp.); tournesol (Fr.); tornesol (Port.)

Authority

• R. J. Gettens, G.L. Stout, R. J. Gettens, G.L. Stout, Painting Materials, A Short Encyclopaedia, Dover Publications, New York, 1966

• Ralph Mayer, Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)

• R.D. Harley, R.D. Harley, Artists' Pigments c. 1600-1835, Butterworth Scientific, London, 1982

• Random House, Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997

• The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 5574

• Art and Architecture Thesaurus Online, http://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000