Difference between revisions of "Carnelian"

Latest revision as of 11:04, 19 December 2022

Lentoid seal
MFA# 1971.173

Description

Carnelian amulets
MFA# 35.1500

A pale orange-red to deep red translucent stone that is a variety of Chalcedony. Carnelian was mined or gathered as an ornamental stone since at least 3000 BCE. It is found in Egypt, India and areas of Europe as water-worn pebbles. Carnelian was popular for amulets and scarabs and is still used as gemstones.

Carnelian cabochon

Synonyms and Related Terms

sard; cornelian; chalcedony; Karneol (Deut., Pol.); cornaline (Fr.); cornalina (Esp., Port.)

Physical and Chemical Properties

No visible crystals
Fracture = conchoidal, uneven, splintery
Cleavage = absent
Luster = waxy to vitreous
Streak = white
Fluorescence = generally inert
Pleochroism = absent

Composition	SiO2
Mohs Hardness	6.5-7.0
Density	2.58-2.68 g/ml
Refractive index	1.535 - 1.539
Birefringence	0.003 - 0.009

Comparisons

Properties of Common Gemstones

Resources and Citations

Mineralogy Database: Quartz
Encyclopedia Britannica, http://www.britannica.com Comment: "carnelian." Accessed 14 Sept. 2001 .
Gem Identification Lab Manual, Gemological Institute of America, 2016.
C.W.Chesterman, K.E.Lowe, Audubon Society Field Guide to North American Rocks and Minerals, Alfred A. Knopf, New York, 1979
Wikipedia: Carnelian (Accessed Sept. 14, 2005 and Dec 2022)

@@ Line 1: / Line 1: @@
-[[File:1971.173-84-4.jpg|thumb|]]
+[[File:1971.173-84-4.jpg|thumb|Lentoid seal<br>MFA# 1971.173]]
 == Description ==
+[[File:35.1500-CR6505-d1.jpg|thumb|Carnelian amulets<br>MFA# 35.1500]]
-A pale orange-red to deep red translucent stone that is a variety of [http://cameo.mfa.org/materials/fullrecord.asp?name=chalcedony chalcedony]. Carnelian was mined or gathered as an ornamental stone since at least 3000 BCE. It is found in Egypt, India and areas of Europe as water-worn pebbles. Carnelian was popular for amulets and scarabs and is still used as gemstones.
+A pale orange-red to deep red translucent stone that is a variety of [[chalcedony]]. Carnelian was mined or gathered as an ornamental stone since at least 3000 BCE. It is found in Egypt, India and areas of Europe as water-worn pebbles. Carnelian was popular for amulets and scarabs and is still used as gemstones.
+[[File:image9_carnelian.jpg|thumb|Carnelian cabochon]]
 == Synonyms and Related Terms ==
 sard; cornelian; chalcedony; Karneol (Deut., Pol.); cornaline (Fr.); cornalina (Esp., Port.)
-[[File:35.1500-CR6505-d1.jpg|thumb|]]
+== Physical and Chemical Properties ==
-== Other Properties ==
-Trigonal crystal system  Fracture = conchoidal.  Luster = vitreous to waxy.  Streak = white.
+* No visible crystals
+* Fracture = conchoidal, uneven, splintery
+* Cleavage = absent
+* Luster = waxy to vitreous
+* Streak = white
+* Fluorescence = generally inert
+* Pleochroism = absent
 {| class="wikitable"
@@ Line 19: / Line 24: @@
 |-
 ! scope="row"| Mohs Hardness
-| 7.0
+| 6.5-7.0
 |-
 ! scope="row"| Density
-| 2.6
+| 2.58-2.68 g/ml
+|-
+! scope="row"| Refractive index
+| 1.535 - 1.539
+|-
+! scope="row"| Birefringence
+| 0.003 - 0.009
 |}
-== Additional Information ==
-Mineralogy Database: [http://www.webmineral.com/data/Quartz.shtml Quartz]
-[[File:image9_carnelian.jpg|thumb|Carnelian cabochon]]
 == Comparisons ==
 [[media:download_file_464.pdf|Properties of Common Gemstones]]
+==Resources and Citations==
+* Mineralogy Database: [http://www.webmineral.com/data/Quartz.shtml Quartz]
-== Authority ==
+* ''Encyclopedia Britannica'', http://www.britannica.com  Comment: "carnelian." Accessed 14 Sept. 2001 .
+* Gem Identification Lab Manual, Gemological Institute of America, 2016.
-* ''Encyclopedia Britannica'', http://www.britannica.com  Comment: "carnelian." Encyclopædia Britannica. 14 Sept. 2001 .
 * C.W.Chesterman, K.E.Lowe, ''Audubon Society Field Guide to North American Rocks and Minerals'', Alfred A. Knopf, New York, 1979
+* Wikipedia: [https://en.wikipedia.org/wiki/Carnelian Carnelian] (Accessed Sept. 14, 2005 and Dec 2022)
-* Wikipedia, the free encyclopedia, at http://www.wikipedia.com  Comment: http://en.wikipedia.org/wiki/Carnelian (Accessed Sept. 14, 2005)
 [[Category:Materials database]]