|
Click on a
letter above to view the list of gems. |
|
| Chemistry:
Na2SO4
[Sodium Sulfate] | Discovered
in 1826;
IMA
status: Valid (pre-IMA; Grandfathered). Thénardite
is named in honor of Professor Louis Jacques Thénard
(1777–1857), French chemist, University of Pierre and
Marie Curie, Paris, France. |
|
Classification
|
|
|
Mineral
Classification: |
Sulfates |
Strunz 8th
Ed. ID:
|
6/A.07-10
|
Nickel-Strunz 10th
Ed. ID:
|
7.AC.25 |
|
7 : SULFATES (selenates, tellurates, chromates, molybdates,
wolframates) A : Sulfates (selenates, etc.) without additional anions,
without H2O C : With medium-sized and large cations
|
Related
to: |
Thénardite - Mascagnite Series
|
|
|
Crystal
Data
|
|
|
Crystallography:
|
Orthorhombic
- Dipyramidal
|
Crystal
Habit:
|
Crystals
dipyramidal {111}, or tabular {010} with large {101},
rarely prismatic along [100], to 20 cm; as pulverulent
crusts and efflorescences
|
Twinning:
|
On
{110}, commonly forming cruciform groups; as crude butterflylike
twins on {011}
|
|
|
Physical
Properties
|
|
|
Cleavage: |
[010]
Perfect, [101] Fair, [100] Interrupted
|
Fracture: |
Splintery,
Uneven to Hackly
|
Tenacity:
|
Somewhat
Brittle
|
Hardness
(Mohs): |
2.5
- 3.0
|
Density:
|
2.664
- 2.700 (g/cm3)
|
Luminescence:
|
Fluorescent;
SW UV = white,
LW UV = yellow-green |
Radioactivity:
|
Not
Radioactive
|
Other: |
Easily
soluble in water
|
|
|
Optical
Properties
|
|
|
Color: |
Colorless;
Grayish White, pale Yellow, Yellow-Brown, Reddish due
to inclusions
|
Transparency: |
Transparent
to Translucent |
Luster: |
Vitreous
to Resinous |
Refractive
Index: |
1.471
- 1.484
Biaxial ( + )
|
Birefringence: |
0.0013
|
Dispersion: |
Weak to None;
r > v |
Pleochroism: |
None |
|
|
Occurances
|
|
|
Geological
Setting: |
Typically
in lacustrine (salt and soda lake) evaporite deposits
in arid regions, also as crusts and efflorescences,
which may be ephemeral, in a wide range of geologic
environments; as precipitates around fumaroles. |
Common
Associations: |
Blödite,
Epsomite, Glauberite, Gypsum, Halite, Mirabilite, Natron |
Type
Locality: |
Espartinas Salt Lake, Aranjuez, Madrid, Spain |
Year
Discovered: |
1826
|
View
mineral photos: |
Thénardite
Mineral Photos and Locations |
|
|
More
Information
|
|
|
|
Mindat.org Webmineral.com |
|
|
Thénardite
is a rare sulfate mineral that is rarely found
as crystals large enough for faceting. It is one of
several arid region, non-marine evaporate sulfate
minerals and is associated with other minerals that
form in the deposits of playa lakes. Thénardite is readily
water soluble and should be stored carefully.
There
are numerous minor occurrences of Thénardite but rarely
in thick beds or as large crystals. Two notable localities
for relatively large crystals are from Searles Lake,
San Bernardino County, California, USA and Bärenstein Quarry, Niederschlag, Oberwiesenthal,
Erzgebirge, Saxony, Germany.
|
Thénardite
gems for sale:
We
have not photographed our Thénardite gems. Please
check back soon.
|
|