Pirus

Pirus merupakan mineral tidak tembus cahaya berwarna toska yang dianggap sebagai batuan berharga karena warnanya yang unik. Istilah pirus berasal dari kata bahasa arab Fairuz (فيروز).

Referensi

Bacaan lanjut 

 British Museum (2000). Aztec turquoise mosaics. Retrieved November 15, 2004 from www.thebritishmuseum.ac.uk
 Dietrich, R. V. (2004). Turquoise. Retrieved November 20, 2004 from www.cst.cmich.edu/users/dietr1rv/turquoise.htm
 Persian Turquoise Mine  
 King, R. J. (2002) Turquoise. Geology Today 18 (3), pp. 110–114. Retrieved November 24, 2004, from: http://doi.org/10.1046/j.1365-2451.2002.00345.x
 Pogue, J. E. (1915). The turquoise: a study of its history, mineralogy, geology, ethnology, archaeology, mythology, folklore, and technology. National Academy of Sciences, The Rio Grande Press, Glorieta, New Mexico. ISBN 0-87380-056-7
 Schadt, H. (1996). Goldsmith's art: 5000 years of jewelry and hollowware. Arnoldsche Art Publisher, Stuttgart, New York. ISBN 3-925369-54-6
 Schumann, W. (2000). Gemstones of the world, revised edition. Sterling Publishing. ISBN 0-8069-9461-4
 Webster, R. (2000). Gems: Their sources, descriptions and identification (5th ed.), pp. 254–263. Butterworth-Heinemann, Great Britain. ISBN 0-7506-1674-1

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