Our navigation bar is loading . . . . . .


Advertise on JCSM - Hear JCSM's Weekly Devotions via Podcast/RSS Feed! - Skip These Ads

You can advertise your site right here!Click here to learn more!

 10,000 Wise Quotes and Spiritual Sayings by Jason Gastrich, Ph.D.

 JCSM's Top 1000 Christian Sites - Free Traffic Sharing Service! Join the Online Christ-Centered Ministries!

-
Jesus Christ Saves Ministries

Click here and add this page to your favorites!

Return to the JCSM Study Center!

Encyclopedia Britannica



DIOPTASE

This article appears in Volume V08, Page 289 of the Encyclopedia Britannica.

Encyclopedia Britannica - Main :: DIO-DRO
DIOPTASE , a rare
mineral
  species consisting of acid copper orthosilicate, H2CuSiO4, crystallizing in the parallel-faced herniahedral class of the rhombohedral
system
 . The degree of sym-
metry is the same as in the
mineral
  phenacite, there being orly ar
axis
  of triad symmetry and a centre of symmetry. The crystals have the form of a hexagonal prism m terminated by a rhombohedron r, the alternate edges between these being sometimes re-placed by the faces of a rhombohedron s. The faces are striated parallel to the edges between r, s and in. There are perfect cleavages parallel to the faces of a rhombohedron which truncate the polar edges of r: from the cleavage cracks internal reflections are often to be seen in the crystal, and it was on account of this that the mineral was named dioptase, by
R. J. Hauy in 1797, from Sioirrciav, " to see into." The crystals vary from transparent to translucent with a vitreous lustre, and are
bright
 
emerald
 -green in colour; they thus have a certain resemblance to
emerald
 , hence the early name emerald-copper (German, Kupfer-Smaragd). Hardness 5; sp. gr. 3.3. The mineral is decomposed by hydrochloric acid with separation of gelatinous
silica
 . At a red heat it blackens and gives off water. The fine crystals from
Mount
  Altyn-Tube on the western slopes of the Altai Mountains in the Kirghiz
Steppes
 , Asiatic Russia, line cavities in a compact limestone; they were first sent to Europe in 1785 by Achir Mahmed, a Bucharian merchant, after whom the mineral has been named archirite. More recently, in 189o, good crystals of similar habit, but rather darker in colour, have been found with
quartz
  and malachite near Komba in the French Congo. As drusy crystalline crusts it has! been found at Copiapo in Chile and in Arizona.
Dioptase has occasionally been used as a gem-stone, especially in Russia and Persia; it has a fine colour, but a low degree of hardness and the transparency is imperfect. (L. J. S.)


End of Article: DIOPTASE


If you wish, you can link directly to this article.
<a href="http://jcsm.org/StudyCenter/Encyclopedia/DIO_DRO/DIOPTASE.html">
DIOPTASE
</a>
(Previous)
DIOPSIDE 		(Next)
DIORITE (from the Gr. S&oi4eiv to distinguish, ...

 


 

Jesus Christ Saves Ministries

The JCSM Study CenterAmerica's Christian FoundationSkeptic's Annotated Bible: Corrected and ExplainedNKJV Web Hosting and Services
JCSM's Sermons, Debates and the Bible on MP3The Online Christ-Centered MinistriesDo You Have A Web Site?  Your Ad Could Be Here!Seminary Notes and PapersThe Picturesque Photo Albums


Jesus Christ Saves Ministries, P.O. Box 70696, Pasadena, CA 91117

JCSM is a 501(c)(3), non-profit organization. Copyright © 1997-present.


Kingdom Debt Solutions - Be Debt Free! Sport Logos - Quality Athletic Equipment The JCSM Study Center Your Ad Could Be Here! Launch A Successful Internet Organization or Business! Learn Guitar, Bass, or Piano in San Diego county!

You can advertise your site right here!

Free & Cheap Cell Phones  |  Cheap Long Distance Phone Service Carriers  |  Talk America Local Phone Service  |  Ztel & MCI - Unlimited Long Distance
Compare Cell Phone Plans & Companies  |  International Calling Cards & Prepaid Phone Cards  |  Voice Over IP Broadband Internet Phone Service  |  Wireless Phone Plans & Cheap Cell Phones

Dr. Jason Gastrich

Jason Gastrich, Ph.D.

 

Jesus Christ Saves Ministries is directed by Dr. Jason Gastrich.  It was founded in 1997 and it exists to bring people into a life-changing and productive relationship with Jesus Christ.  JCSM offers over 200,000 free web pages, discussion boards, weekly html and mp3 devotionals, free email accounts, and much more.

Jesus Christ Saves Ministries
P.O. Box 9297
San Diego, CA  92169
1-877-850-3878 or Email

JCSM is a 501(c)(3), non-profit organization. Copyright © 1997-2008.

_____________________________________________________________________________

Online First Aid and CPR Certification  .  The Online Christ Centered Ministries  .  The Skeptic's Annotated Bible: Corrected and Explained  .  The Inerrancy Discussion Board  .  Free Email Accounts  .  Home Equity Loans  .  JasonGastrich.com  .  The Missions, Apologetics, and Creation Bible Conference  .  Young Earth Creation Science  .  San Diego Music Lessons  .  10,000 Wise Quotes and Spiritual Sayings  .  Gastrich.net  .  Maximizing the Internet: 12 Keys to Success  .  Louisiana Baptist University  .  NKJV Web Hosting and Services  .  Michael Newdow  .  San Diego Soccer Training  . Christian Guitar Lessons  .  Jesus Christ Saves Ministries  .  Eternal Security