Physical Properties of Ore Minerals

Table 6. Tetragonal Crystal Class

Minerals are arranged alphabetically by space group (Schoenflies symbol).

If you want to print this table please use landscape mode.

Mineral Name	Composition	Space Group	Resistivity (ohm-m)	Dielectric Permittivity	Charge Separation Phenomena	Curie Temp. °C	Magnetic Properties k×10-6cgs	Optical Properties	R %	Comments
Nagyagite	Pb5Au(Te,Sb)4S5--8 Au(Pb,Sb,Fe)8(Te,S)4	S41	semiconductor 10-5 to 10-4		piezoelectric			weak pleochroism, distinct anisotropy, weak bireflectance.	38.6 to 42.6	Ramdohr (1980) says crystal class is monoclinic, pseudo-tetragonal.
Mooihoekite	Cu9Fe9S16	D2d1	semiconductor		piezoelectric		antiferromagnetic	no data	25.5 to 30.8?	Forms solid solution with chalcopyrite.
Renierite	Cu3(Fe,Ge)S4	D2d9	semiconductor		piezoelectric ferroelectric??			rare pleochroism, distinct to strong anisotropy, distinct bireflectance.	24.4 to 24.9
Stannite	Cu2FeSnS4	D2d9	semiconductor 10-3 to 6×103		piezoelectric ferroelectric??	<706		distinct pleochroism, moderate anisotropy, weak to strong bireflectance.	Ro-27.3 Re-26.0	Forms solid solution with kesterite, hocarite, briartite, mawsonite, sakuraiite, and others.
Briartite	Cu2(Fe,Zn)GeS4	D2d11	semiconductor		piezoelectric		antiferromagnetic Tn = 12°K	weak to distinct bireflectance, distinct anisotropism.	27.5	See stannite.
Kesterite	Cu2ZnSnS4	D2d11	semiconductor		piezoelectric ferroelectric??			indistinct pleochroism, distinct anisotropy.	23.3 to 24.3	See stannite.
Luzonite Stibioluzonite	Cu3AsS4 Cu3SbS4	D2d11	semiconductor ~10-2		piezoelectric ferroelectric ?		diamagnetic	twinning accentuates pleochroism, very strong anisotropy, distinct to strong bireflectance.	Ro-23.8 Re-27.9	Forms solid solution with stibioluzonite.
Permingeatite	Cu3SbSe4	D2d11			piezoelectric ferroelectric??			strongly anisotropic	Ro-25.2 Re-24.8
Sakuraiite	(Cu,Zn,Fe)3InS4	D2d11	semiconductor		piezoelectric ferroelectric??			indistinct pleochroism, weak to distinct anisotropy.	22.3
Chalcopyrite	CuFeS2	D2d12	semiconductor n-type 10-5 to 150 large decrease at T ~ 330°C		ferroelectric ? (isostructural)	<550	antiferromagnetic k~32 Tn =277°C	weak pleochroism, weak but distinct anisotropy, weak bireflectance.	Ro-44.4 Re-45.3	Forms solid solution with bornite, cubanite, haycockite, mooihoekite, pyrite, and talnakhite. Measurable surface charge on crystal faces at 25°C.
Gallite	CuGaS2	D2d12	semiconductor		ferroelectric ? (isostructural)			rare pleochroism, distinct anisotropy, distinct bireflectance in oil.	17.6
Roquesite	CuInS2	D2d12	semiconductor		ferroelectric ? (isostructural)			low bireflectance, distinct anisotropism.	22.3 to 23.4
Russelite	Bi2WO6	D2d12			ferroelectric Lines and Glass (1977)	950		no data	OT
Mackinawite	(Fe,Ni,Co...)S Fe1+xS	D4h7	metal		ferroelectric??	<153	Pauli paramagnetic	enormous bireflectance, extreme anisotropism.	21.7 to 46.3
Rickardite	Cu4Te3 or Cu4-xTe2	D4h7			ferroelectric??			striking pleochroism, extremely anisotropic, very strong bireflectance.	13.8 to 18.3	Compares optically with umangite.
Cassiterite	SnO2	D4h14	semiconductor n-type 4.5×10-4 to 104	9<e<105	ferroelectric Deshpande and Bhide (1961)	~ 5	diamagnetic or paramagnetic ? k = -41 to 90	extreme birefringence, in reflected light shows weak pleochroism, strong anisotropy, and weak bireflectance.	OT Ro-11.5 Re-12.4
Plattnerite	PbO2	D4h14	semiconductor 10-6	26	ferroelectric ? (isostructural)			weak pleochroism, very distinct anisotropy, internal reflections always.	19.4 to 19.9
Polianite- pyrolusite	MnO2	D4h14	semiconductor n-type 10-5 to 1.6×102	104<e<105	ferroelectric Bhide and Damle (1960)	~50	antiferromagnetic k = 2,300 Tn = 84°K	weak bireflectance, distinct pleochroism, very strong anisotropy.	Ro-29.0 Re-40.0	Ferroelectricity not confirmed by Yousef and Farag (1965) on samples from a different area.
Rutile	TiO2	D4h14	semiconductor 29 to 109	79<e<5×104	ferroelectric Niccolini (1959)	300	diamagnetic k = -30 to +6	distinct anisotropy, distinct internal reflections, prominent twinning, distinct bireflectance, weak to strong pleochroism, very extreme birefringence.	20.3	Stoichiometric TiO2 is not ferroelectric according to Jona and Shirane (1962).
Umangite	Cu3Se2	D4h14			ferroelectric ? (isostructural)			very strong and striking pleochroism, very strong anisotropy and bireflectance, distinctive twin lamellae.	Ro-12.2 Re-16.6	One of the most unusual and beautiful minerals in ore microscopy.
Hausmannite	Mn3O4	D4h19			ferroelectric??		k = 12,400	strong anisotropy, distinct bireflectance, extreme birefringence.	Ro-19.6 Re-17.6
Jalpaite	Ag3CuS2	D4h19			ferroelectric??	<117		very weak pleochroism, distinctly anisotropic, distinct bireflectance in oil.	30.6 to 33.1	Converts to cubic at 117°C.
Paramelaconite	CuO	D4h19			ferroelectric??		antiferromagnetic k = 255	pronounced bireflectance, distinctly anisotropic.		Crystal structure is deficient in O. Also see tenorite under monoclinic.
Braggite and vysotskyite	(Pt,Pd,Ni)S (Pd,Ni)S	C43	semiconductor		pyroelectric ferroelectric??			weak bireflectance, extreme anisotropy, distinct bireflectance in oil.	41.6 to 43.0 ~45	Optical properties vary with composition.
Makedonite	PbTiO3	C4v1			ferroelectric Shirane et al. (1950)	490		no data	20.8	Rare in nature.

Return to Zonge International Home Page