Manila copal

Manila copal on glass (Visible light on left, UV light on right)

Description

A soft variety of Copal resin obtained from the Agathis dammara trees native to the Philippines and Indonesia. Manila copal is a diterpenoid resin composed primarily of polycommunic acid. Copals were used in the 18th and 19th centuries for varnishes and resin/oil media. Manila copals were also used in many Fixative recipes.

Synonyms and Related Terms

Agathis dammara; manilla copal (Br.); copal de Manila (Esp.); copale di Manila (It); Manila resin; manilla

Risks

• Combustible, burning with a bright flame, dense smoke and strong smell.

Physical and Chemical Properties

• Soluble in ether, methanol, and ethanol. Partially soluble in amyl alcohol. Insoluble in water.
• Most copals fluoresce white in short-wave UV light.
• Saponification number = 178
• Acid number = 128.
• Melting Point = 230-250 C
• Density = 1.062 g/ml
• Refractive Index = 1.544

Resources and Citations

• K.van den Berg, J.van der Horst, J.Boon, "Recognition of Copals in Aged Resin/oil Paints and Varnishes" in ICOM Preprints, Lyon, 1999. p.855-861.

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

• G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 227; synonym Boea copal

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

• Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993

• Encyclopedia Britannica, http://www.britannica.com Comment: "Copal." Accessed 14 Apr. 2004.

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

• "Copal: An Immature and Controversial Resin" at www.emporia.edu/earthsci/amber/copal.htm