Potch - Hutchinson encyclopedia article about Potch Printer Friendly
The Free Dictionary
1,074,251,150 visitors served.
?
Dictionary/
thesaurus
Medical
dictionary
Legal
dictionary
Financial
dictionary
Acronyms
 
Idioms
Encyclopedia
Wikipedia
encyclopedia
?

opal
(redirected from Potch)

    Also found in: Dictionary/thesaurus, Encyclopedia, Wikipedia 0.10 sec.

opal

Form of hydrous silica (SiO2.nH2O), often occurring as stalactites and found in many types of rock. The common opal is translucent, milk-white, yellow, red, blue, or green, and lustrous. Precious opal is opalescent, the characteristic play of colours being caused by close-packed silica spheres diffracting light rays within the stone.

Opal is cryptocrystalline, that is, the crystals are too fine to be detected under an optical microscope. Opals are found in Hungary; New South Wales, Australia (black opals were first discovered there in 1905); and Mexico (red fire opals).



How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content.
?Page tools
Printer friendly
Cite / link
 Email
Feedback
?Sign in SSL protected
Email:
Password:
Register

? Mentioned in
 
Hutchinson browser? ? Full browser
 
 
Hutchinson Encyclopedia
?

Disclaimer | Privacy policy | Feedback | Copyright © 2008 Farlex, Inc.
All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional.. Terms of Use.