Mindat Logo
Home Page Log In Messageboard The Mindat Directory
Register Search Pages Mineral Chatroom The Mindat Store

Esperite

This page is currently not sponsored. Click here to sponsor this page.
Big Photo

Franklin Mine, Franklin, Franklin Mining District, Sussex Co., New Jersey, USA

Show Esperite Photos (12)



Formula:
PbCa
 
2
Zn
 
3
(SiO
 
4
)
 
3
System:MonoclinicColour:White, off-white, pale ...
Hardness:5
Name:
Named for Esper Signius Larsen, Jr. (March 14, 1879-March 8, 1961), petrologist and Professor of Geology at Harvard University, Cambridge, Massachusetts, USA. (see also Larsenite).
Isostructural with:Beryllonite, Larsenite


Massive off-white material in typical Franklin ore (willemite, zincite, franklinite, calcite) and often with hardystonite, clinohedrite.

Often found pseudomorphically replacing hardystonite, in part as feathery incursions into massive hardystonite, and as complete replacements, including of embedded hardystonite crystals. These features are readily evident under UV light.

Visit gemdat.org for gemological information about Esperite. Currently in public beta-test.

Classification of Esperite

IMA status:Approved 1964
Strunz 8th edition ID:8/A.03-20
Nickel-Strunz 10th (pending) edition ID:9.AB.15

9 : SILICATES (Germanates)
A : Nesosilicates
B : Nesosilicates without additional anions; cations in [4] and greater coordination
Dana 7th edition ID:51.2.1.3
Dana 8th edition ID:51.2.1.3

51 : NESOSILICATES Insular SiO4 Groups Only
2 : Insular SiO4 Groups Only with cations in [4] as well as >[4]
Hey's CIM Ref.:14.7.19

14 : Silicates not Containing Aluminum
7 : Silicates of Ba, Sr and Zn
mindat.org URL:http://www.mindat.org/min-1412.html
Please feel free to link to this page.

Type Occurrence of Esperite

Type Locality:Parker Mine (Parker shaft), Franklin Mine, Franklin, Franklin Mining District, Sussex Co., New Jersey, USA
General Appearance of Type Material:Massive off-white material in massive ore.
Year of Discovery:1928
Geological Setting of type material:Metamorphosed stratiform zinc-iron-manganese orebody.
Associated Minerals at type locality:
ZinciteWillemiteHardystoniteFrankliniteClinohedrite
Calcite

Physical Properties of Esperite

Lustre:Sub-Vitreous, Greasy
Diaphaneity (Transparency):Transparent, Translucent
Colour:White, off-white, pale tan
Streak:White.
Hardness (Mohs):5
Tenacity:Brittle
Cleavage:Distinct/Good
Distinct on {010} and {100}, poor on {101}
Fracture:Irregular/Uneven
Density (measured):4.28 - 4.42 g/cm3
Density (calculated):4.25 g/cm3

Crystallography of Esperite

Crystal System:Monoclinic
Class (H-M):2/m - Prismatic
Space Group:P21/m {P1 1 21/m} {P21/m} {P1 21/m 1}
Cell Parameters:a = 17.628Å, b = 8.27Å, c = 30.52Å
β = 90°
Ratio:a:b:c = 2.132 : 1 : 3.69
Unit Cell Volume:V 4449.31 ų
Z:12
Morphology:Coarse granular aggregates, massive, to 9 cm
X-Ray Powder Diffraction:
d-spacingIntensity
7.62 (45)
3.363 (23)
3.017 (100)
2.884 (33)
2.534 (75)
2.367 (40)
1.944 (45)
Comments:From Franklin, New Jersey material

Optical Data of Esperite

Type:Biaxial (-)
RI values: nα = 1.762 nβ = 1.770 nγ = 1.774
2V:Measured: 5° to 40°
Birefringence:0.012
Maximum Birefringence:δ = 0.012

Chart shows birefringence interference colour range (at 30µm thickness) and does not take into account mineral colouration.
Surface Relief:Very High
Dispersion:very strong

Chemical Properties of Esperite

Formula:
PbCa
 
2
Zn
 
3
(SiO
 
4
)
 
3
Essential elements:Ca, O, Pb, Si, Zn
All elements listed in formula:Ca, O, Pb, Si, Zn
Analytical Data:First set based on Pb1.23(Ca2.89Mn0.08Mg0.06)Zn3.73Si3.98O16 and second set based on electron microprobe average of 10 analyses to Pb1.15(Ca2.80Mg0.09Mn0.08)2.97Zn3.80Si4.04O16
SiO2 (24.10),(25.3)
FeO (0.48), 0
MnO (0.57),(0.6)
ZnO (30.61),(32.3)
PbO (27.63),(26.8)
MgO (0.23),(0.4)
CaO (16.36),(16.4)
H2O (0.12)
Common Impurities:Fe,Mn,Mg

Relationship of Esperite to other Species

Related Minerals - Nickel-Strunz Grouping):

- +
9.AB.05Trimerite
CaMn
2+
2
Be
 
3
(SiO
 
4
)
 
3
9.AB.10Larsenite
PbZnSiO
 
4
9.AB.20Rondorfite
Ca
 
8
Mg(SiO
 
4
)
 
4
Cl
 
2
Related Minerals - Hey's Index Grouping:

- +
14.7.1Sanbornite
Ba
 
2
(Si
 
4
O
 
10
)
14.7.2Krauskopfite
BaSi
 
2
O
 
5
 · 3H
 
2
O
14.7.3Walstromite
BaCa
 
2
(Si
 
3
O
 
9
)
14.7.4Macdonaldite
BaCa
 
4
Si
 
16
O
 
36
(OH)
 
2
 · 10H
 
2
O
14.7.5Ericssonite
BaMn
2+
2
Fe
3+
 
(Si
 
2
O
 
7
)O(OH)
14.7.6Ericssonite-2O
BaMn
2+
2
Fe
3+
 
(Si
 
2
O
 
7
)O(OH)
14.7.7Gillespite
BaFe
2+
 
[Si
 
4
O
 
10
]
14.7.8Andrémeyerite
BaFe
2+
2
(Si
 
2
O
 
7
)
14.7.9Pellyite
Ba
 
2
Ca(Fe,Mg)
 
2
Si
 
6
O
 
17
14.7.10Taikanite
Sr
 
3
BaMn
2+
2
(Si
 
4
O
 
12
)O
 
2
14.7.11Willemite
Zn
 
2
SiO
 
4
14.7.12Hemimorphite
Zn
 
4
Si
 
2
O
 
7
(OH)
 
2
 · H
 
2
O
14.7.13Zincsilite
Zn
 
3
(Si
 
4
O
 
10
)(OH)
 
2
 · 4H
 
2
O
14.7.14Hardystonite
Ca
 
2
Zn(Si
 
2
O
 
7
)
14.7.15Petedunnite
Ca(Zn,Mn
2+
 
,Mg,Fe
2+
 
)Si
 
2
O
 
6
14.7.16Clinohedrite
CaZn(SiO
 
4
) · H
 
2
O
14.7.17Junitoite
CaZn
 
2
Si
 
2
O
 
7
 · H
 
2
O
14.7.18Larsenite
PbZnSiO
 
4
14.7.20Hodgkinsonite
Mn
2+
 
Zn
 
2
(SiO
 
4
)(OH)
 
2
14.7.21Gerstmannite
MnMgZn(SiO
 
4
)(OH)
 
2
14.7.22Gageite
Mn
 
21
O
 
3
(Si
 
4
O
 
12
)
 
2
(OH)
 
20
14.7.23Franklinfurnaceite
Ca
 
2
Fe
3+
 
Mn
2+
3
Mn
3+
 
(Zn
 
2
Si
 
2
O
 
10
)(OH)
 
8
Related Minerals - Dana Grouping):

- +
51.2.1.1Trimerite
CaMn
2+
2
Be
 
3
(SiO
 
4
)
 
3
51.2.1.2Larsenite
PbZnSiO
 
4

Other Names for Esperite

Synonyms:
Calcium-LarseniteIMA1964-027
Other Languages:
Dutch:Esperiet
German:Esperit
Italian:Esperite
Spanish:Esperita

Other Information

Fluorescence in UV light:Bright yellow (SW UV)(Franklin); dull yellow (LW UV)
Health Warning:No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.
Industrial Uses:None

References for Esperite

Reference List:

- +
Palache, Charles, L.H. Bauer & H. Berman (1928), Larsenite, calcium-larsenite and associated minerals at Franklin, NJ: American Mineralogist: 13: 334-340.

Palache, Charles (1935), The Minerals of Franklin and Sterling Hill, Sussex County, New Jersey, USGS Professional Paper 180: 81-82.

Moore, Paul B. & Ribbe, P.H. (1965): "Calcium-larsenite" renamed esperite. American Mineralogist, 50, 1170-1178.

Dunn, Pete J. (1985), The lead silicates from Franklin, New Jersey: occurrence and composition: Mineralogical Magazine: 49: 721-727.

Anthony, Bideaux, Bladh & Nichols (1995), Handbook of Mineralogy, Vol. II: Silicates, Mineral Data Publishing: 225.

Gaines, Richard V., H. Catherine, W. Skinner, Eugene E. Foord, Brian Mason, Abraham Rosenzweig, Vandall T. King (1997), Dana's New Mineralogy : The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, 8th. edition. John Wiley & Sons, New York.

Tait, K., Yang, H., Downs, R.T., Li, C., Pinch, W.W. (2010): The crystal structure of esperite, with a revised chemical formula, PbCa2(ZnSiO4)3, isostructural with beryllonite. American Mineralogist, 95, 699-705.

Internet Links for Esperite

Search Engines:
  • Look for Esperite on Google
  • Look for Esperite images on Google
    • External Links:
  • Look for Esperite on Webmineral
  • Look for Esperite on Athena Mineralogy
  • Look for Esperite on Wikipedia
  • Look for Esperite on Mineralien Atlas
  • Raman and XRD data at RRUFF project
  • American Mineralogist Crystal Structure Database
  • Esperite details from Handbook of Mineralogy (PDF)
    • Mineral Dealers:
  • Search for minerals at Heliodor
  • Top quality minerals from Kristalle of California
  • Rare and Unusual minerals at Mineralogical Research Company
  • Fabre Minerals - search for Esperite specimens
  • DAKOTA MATRIX offers Cabinet and Rare Species from Worldwide Localities.
  • Search for Esperite on Well-Arranged Molecules
  • Buy minerals from YourMineralCollection
  • Buy fine minerals and gemstones from Pala International
  • SpiriferMinerals.com - high quality low prices
  • Find Esperite on www.crystalclassics.co.uk
  • webminerals
  • Mineral Classics - Worldwide Collector Quality Minerals and Gems
    • Jobs:
  • Mining & Geology Jobs

    • Localities for Esperite

    The map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.
    Hide Locality List
    (TL) indicates type locality. ? indicates mineral may be doubtful at this locality. All other localities listed without reference should be considered as uncertain and unproven until references can be found.
    Bolivia
     
    • Potosí Department
      • Antonio Quijarro Province
    		[MinRec 21:133]
    USA
     
    • New Jersey
      • Sussex Co.
        • Franklin Mining District
          • Franklin
    		Palache (1935): 81; Dunn( 1995): Pt3: 368.
    Palache (1935): 81; Dunn( 1995): Pt3: 368.
    Mineral and/or Locality
    Search Google
     
    Copyright © Jolyon Ralph and Ida Chau 1993-2013. Site Map. Locality, mineral & photograph data are the copyright of the individuals who submitted them. Further information contact the Site hosted & developed by Jolyon Ralph. Mindat.org is an online information resource dedicated to providing free mineralogical information to all. Mindat relies on the contributions of hundreds of members and supporters. Mindat does not offer minerals for sale. If you would like to add information to improve the quality of our database, then click here to register.
    Current server date and time: 2nd Feb 2013 16:55:44
    Mineral and Locality Search
    Mineral:
    and/or Locality:
    Options
    Fade toolbar when not in focusFix toolbar to bottom of page
    Hide Social Media Links
    Slideshow frame delay seconds