World Library  
Flag as Inappropriate
Email this Article


Article Id: WHEBN0000341821
Reproduction Date:

Title: Spectrolite  
Author: World Heritage Encyclopedia
Language: English
Subject: Ylämaa, Feldspar, Plagioclase, Labradorite, Gemstones
Collection: Feldspar, Gemstones
Publisher: World Heritage Encyclopedia


Spectrolite from Oslo museum
Polished spectrolite showing the color play

Spectrolite is a less common variety of labradorite feldspar.

Spectrolite exhibits a richer range of colours than labradorite (that shows only tones of blue-grey-green) and high labradorescence.[1][2] Spectrolite was initially a brand name for material mined in Finland, but is sometimes incorrectly used to describe labradorite whenever a richer display of colours is present, regardless of locality: for example, labradorite with the spectrolite play of colors has also reported from Madagascar.[1] The difference between Finnish spectrolite and other labradorites is that crystals of the former have considerably stronger colourfulness than other labradorites, caused by the black base color of spectrolite feldspar; other labradorites have mostly a transparent base color. Spectrolite is often cut as a lapidary cabochon, similar to plain labradorite, to enhance the effect and is used as a gemstone.

Finland deposit

Finnish geologist Aarne Laitakari (1890–1975) had described the peculiar stone and sought its origin for years when his son Pekka discovered a deposit at Ylämaa in south-eastern Finland while building the Salpa Line fortifications there in 1940. The Finnish stone exhibits a uniquely vivid iridescence and a full spectrum of colors, hence the name "spectrolite" was coined by the elder Laitakari. The name spectrolite is sometimes incorrectly applied to any labradorite of similar colours.

The quarrying of spectrolite began after the Second World War and has become a significant local industry. In 1973 the first workshop in Ylämaa began cutting and polishing spectrolite for jewels.


Seppo Lahti I.1989 The origin of interference colours in spectrolite (iridescent labradorite).Geologi 41.

  1. ^ a b Michael O'Donoghue, Gems, Butterworth-Heinemann, 6th ed., 2006, pp. 238-267, ISBN 0-7506-5856-8
  2. ^ Walter Schumann, Gemstones of the World, Sterling, 3rd ed., 2007, pp. 52 - 53, 182 ISBN 1-4027-4016-6

This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from World eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.