1.2.3 Biaxial Crystals

Biaxial

Density

Hardness

Cleavage

Solubility (ºC)

material

(g/cm3)

(kg/mm2)

plane

(g/100 g H2O)

Al2(MoO4)3

3.495

–

–

Insoluble

Al2(WO4)3

5.079

–

(010)-p

Insoluble

Al2Ge2O7

4.06

–

–

Insoluble

Al2SiO4F2

3.57

8 (Mohs)

(001)-p

Insoluble

Al2SiO5-andalusite

3.13

6.5 (Mohs)

(110)

Insoluble

Al2SiO5-kyanite

3.6

4–7.5 (Mohs)

(100)-p

Insoluble

Al2SiO5-sillimanite

3.25

6.5 (Mohs)

(010)-p

Insoluble

Al4B2O9

2.904

–

–

–

Al6Ge2O13

3.662

–

–

Insoluble

Al6Si2O13

3.19

1750

(010)-i

Insoluble

AlHfTaO6

8.33

–

–

Insoluble

AlNb11O29

4.46

–

–

Insoluble

AlNbO4

4.673

–

–

Insoluble

AlTaO4

6.86

–

–

Insoluble

As2S3

3.49

1.5 (Mohs)

(010)-p

Insoluble

AsS

3.56

1.5 (Mohs)

(010)-i

Insoluble

AsSbS3

3.92

1.5 (Mohs)

(001)-p

Insoluble

Ba2CaMgAl2F14

4.204

3.5 (Mohs)

(001)-p

Ba2CdMgAl2F14

4.735

–

–

–

Ba2LiNb5O15

–

–

–

Insoluble

Ba2NaNb5O15

5.41

–

–

Insoluble

Ba2Zn3F10

5.26

–

–

–

Ba2ZnAlF9

4.909

–

–

–

Ba2ZnGaF9

5.169

–

–

–

Ba3Al2F12

4.37

–

–

–

Ba3TiAl10O20

4.13

–

–

–

BaAl2B2O7

3.559

–

–

–

BaAl2Ge2O8

–

–

–

Insoluble

BaAl2Si2O8

3.96

6–6.5 (Mohs)

(001)-p

Insoluble

BaBe2Si2O7

4.00

7 (Mohs)

(001)(100)-p

Insoluble

BaCa2Mg(SiO4)2

3.974

–

–

Insoluble

BaCa2Si3O9

3.73

3.5 (Mohs)

(011)(010)-p

Insoluble

BaCdAlF7

5.04

–

–

–

BaCdGaF7

5.406

–

–

–

BaCO3

4.31

3.5 (Mohs)

(010)-i

Very slightly soluble

BaGaF5

5.104

–

–

–

BaGe2O5

5.85

–

–

Insoluble

BaGeAl6O12

4.031

–

–

–

BaGeGa6O12

5.201

–

–

–

Biaxial

Density

Hardness

Cleavage

Solubility (ºC)

material

(g/cm3)

(kg/mm2)

plane

(g/100 g H2O)

BaGeO3

5.072

–

–

Insoluble

BaMgF4

4.538

–

–

–

BaNb2O6

–

–

–

Insoluble

BaSO4

4.50

3 (Mohs)

(001)-p

Insoluble

BaTa2O6

7.824

–

–

Insoluble

BaTi4O9

4.52

–

–

Insoluble

BaTiAl6O12

3.791

–

–

–

BaTiGa6O12

4.981

–

–

–

BaY2F8

5.047

250–350

–

–

BaY2O4

5.806

–

–

–

BaZnF4

5.178

–

–

–

β-BaSi2O5

3.77

5 (Mohs)

(001)

Insoluble

β-Ca2SiO4

3.31

6 (Mohs)

(100)-i

Insoluble

Be2BO3F

2.37

7.5 (Mohs)

(010)-p

Insoluble

BeAl2O4

3.75

1600–2300 (V)

None

Insoluble

BeAl6O10

3.75

–

–

–

β-Ga2O3

5.95

–

(010)-p

Insoluble

Bi2Al4O9

6.229

–

–

–

Bi2GeO5

–

–

–

Insoluble

Bi2Mo2O9

6.518

–

–

Insoluble

Bi2Mo3O12

6.196

–

(100)-p

Insoluble

Bi2O3

9.37

–

–

Very slightly soluble

Bi2SiO5

–

–

–

Insoluble

Bi2WO6

7.35

3.5 (Mohs)

–

–

Bi3TiNbO9

–

–

–

Insoluble

Bi4B2O9

8.185

–

–

–

Bi4Ti3O12

8.045

313

–

Insoluble

γ-Bi2MoO6

7.068

–

–

–

BiB3O6

5.03

5–5.5 (Mohs)

–

Insoluble

BiNbO4

–

–

–

Insoluble

BiSbO4

8.48

–

–

Insoluble

BiTaO4

8.958

–

–

Insoluble

BiVO4-clinobisvanite

6.95

–

–

–

BiVO4-pucherite

6.63

4 (Mohs)

(001)-p

–

Ca(IO3)2

4.48

3.5 (Mohs)

(011)-i

–

Ca2(AsO4)Cl

–

–

(010)-p

–

Ca2(PO4)Cl

–

–

(010)-p

–

Ca2(PO4)F

–

–

(010)-p

Insoluble

Ca2(VO4)Cl

3.075

–

(010)-p

–

Ca2Al2O5

3.73

–

–

–

Ca2B6O11

2.85

–

–

–

Ca2BO3Cl

2.766

–

–

–

Biaxial

Density

Hardness

Cleavage

Solubility (ºC)

material

(g/cm3)

(kg/mm2)

plane

(g/100 g H2O)

Ca2Nb2O7

–

–

–

Insoluble

Ca2Sb2O7

5.204

–

–

Insoluble

Ca2V2O7

3.36

5.5 (Mohs)

(110)-p

–

Ca3(VO4)2

3.16

–

(110)(001)-p

–

Ca3Al2O6

3.017

–

–

–

Ca3Ga4O9

4.208

–

–

–

Ca3MgSi2O8

3.31

6 (Mohs)

None

Insoluble

Ca3Si2O7

2.96

5.5 (Mohs)

–

Insoluble

Ca5Al6O14

3.03

–

(001)-p

–

Ca5Ga6O14

4.18

5 (Mohs)

–

–

CaAl2F8

2.89

4.5 (Mohs)

(111)-p

Insoluble

CaAl2O4

2.942

–

–

–

CaAl2Si2O8

2.76

6–6.5 (Mohs)

(001)-p

Insoluble

CaAl4O7

2.894

8.5 (Mohs)

–

–

CaAlB3O7

3.44

7.5 (Mohs)

None

Insoluble

CaAlBO4

2.60

–

–

–

CaB2O4

2.702

–

–

–

CaB2Si2O8

3.00

7 (Mohs)

None

Insoluble

CaB3O5F

2.729

–

–

Insoluble

CaB4O7

2.69

–

–

–

CaBa(CO3)2

3.67

4 (Mohs)

(110)-i

Very slightly soluble

CaBe(PO4)F

2.95

5 (Mohs)

(110)-i

Insoluble

CaBe2(PO4)2

2.89

6 (Mohs)

None

Insoluble

CaCO3-aragonite

2.93

3.5–4 (Mohs)

(010)-i

Very slightly soluble

CaGa2O4

4.333

–

–

–

CaGe2O5

4.868

–

–

Insoluble

CaIn2O4

6.15

–

–

–

CaMg(PO4)F

–

–

–

Insoluble

CaMgAsO4F

3.77

5 (Mohs)

(101)-i

Very slightly soluble

CaMgB2O5

3.02

4.5 (Mohs)

(010)-p

Very slightly soluble

CaMgGe2O6

4.265

–

–

Insoluble

CaMgSi2O6

3.26

6.5 (Mohs)

(110)-i

Insoluble

CaMgSiO4

3.06

5.5 (Mohs)

(010)-i

Insoluble

CaNb2O6

4.78

5.5 (Mohs)

None

Insoluble

CaSc2O4

3.897

–

–

Insoluble

CaSiO3

2.9

5 (Mohs)

(100)-p

Insoluble

CaSnO3

5.759

–

–

Insoluble

CaSnSiO5

4.56

4 (Mohs)

–

Insoluble

CaSO4

2.96

3.5 (Mohs)

(010)(100)

Very slightly soluble

CaTa2O6

–

–

–

Insoluble

CaTiO3

4.04

–

–

Insoluble

CaTiSiO5

3.53

5.5 (Mohs)

(110)-i

Insoluble

CaV2O6

3.59

–

(100)(001)-p

–

Biaxial

Density

Hardness

Cleavage

Solubility (ºC)

material

(g/cm3)

(kg/mm2)

plane

(g/100 g H2O)

CaYBO4

3.783

–

–

–

CaZnGe2O6

4.807

–

–

Insoluble

CaZnSiO4

4.25

5 (Mohs)

(010)(100)

Insoluble

CaZrSi2O7

3.63

–

–

Insoluble

CaZrTi2O7

4.407

–

–

Insoluble

Cd2B2O5

5.24

–

–

–

Cd2GeO4

6.313

–

–

Insoluble

CdB4O7

3.51

–

–

–

CdWO4

8.005

–

–

–

Cs2BeF4

4.128

–

–

–

Cs2CdBr4

4.069

–

–

–

Cs2HgI4

4.357

–

–

–

Cs2MgCl4

2.952

–

–

–

Cs2ZnBr4

4.034

–

–

–

Cs2ZnCl4

3.357

–

–

–

CsB3O5

3.39

–

–

Soluble

CsGd(MoO4)2

–

–

(100)-p

–

CsLiBeF4

3.411

–

–

–

CsLiSO4

3.455

–

–

Very soluble

CsNbB2O6

–

–

(001)-p

Insoluble

CsLiSO4

3.455

–

–

Very soluble

CsNbB2O6

–

–

(001)-p

Insoluble

CsTiOAsO4

4.511

–

None

Insoluble

CsZnAlF6

4.04

–

–

–

Ga2(WO4)3

–

–

(010)-p

–

Ga2GeO5

4.97

–

–

Insoluble

GaNbO4

5.01

–

–

Insoluble

Gd(BO2)3

4.84

–

–

–

Gd2(MoO4)3

4.65

–

–

–

Gd2(WO4)3

7.475

–

–

–

Gd2GeO5

–

–

–

Insoluble

Gd2MoO6

7.068

–

–

–

Gd2O2SO4

6.483

–

–

–

Gd2O3

8.33

–

–

–

Gd2SiO5

6.77

6 (Mohs)

(100)-p

Insoluble

Gd2Sr3(BO3)4

5.266

–

–

–

Gd2WO6

8.339

–

–

–

Gd3NbO7

7.459

–

–

Insoluble

Gd3TaO7

8.414

–

–

Insoluble

Gd4Al2O9

6.467

–

–

–

α-Ga4GeO8

5.65

–

–

Insoluble

GdAlGe2O7

–

–

–

Insoluble

GdAlO3

7.437

–

–

Insoluble

Biaxial

Density

Hardness

Cleavage

Solubility (ºC)

material

(g/cm3)

(kg/mm2)

plane

(g/100 g H2O)

GdGaGe2O7

6.08

–

–

Insoluble

GdMgB5O10

4.309

–

–

–

GdNbO4

–

–

–

Insoluble

GdP5O14

3.55

–

–

Insoluble

GdPO4

5.986

470

–

Insoluble

GdScO3

6.642

–

–

Insoluble

HfO2

10.11

–

–

Insoluble

HgCl2

5.490

–

–

–

HgO

11.14

1.5–2.0 (Mohs)

(010)-p

–

HIO3

4.637

–

–

–

In2(MoO4)3

3.92

–

–

–

In2(WO4)3

5.619

–

(010)-p

–

InCaBO4

4.536

–

–

–

InGaO3

6.447

–

–

–

InNbO4

6.27

–

(010)-p

Insoluble

InPO4

4.830

–

–

Insoluble

InTaO4

8.296

–

(010)-p

Insoluble

InVO4

4.50

–

–

Insoluble

K2CaSiO4

2.865

–

–

Insoluble

K3Gd(VO4)2

3.15

–

–

Slightly soluble

K3La(PO4)2

5.293

–

–

Insoluble

K3Lu(VO4)2

3.15

–

–

Slightly soluble

K3Y(VO4)2

3.15

–

–

Slightly soluble

KAlSi3O8

2.57

6 (Mohs)

(001)-p

Insoluble

KAl3Si3O10(OH)2

2.78

–

–

Insoluble

KBF4

2.51

–

–

Slightly soluble

KB5O8•4H2O

1.740

2.5 (Mohs)

(010)-p

–

KGaSi3O8

2.887

–

–

Insoluble

KIn(MoO4)2

4.17

–

–

–

KLaP4O12

–

–

–

Insoluble

KLu(WO4)2

7.759

–

–

–

KNbB2O6

3.151

–

(001)-p

Insoluble

KNbO3

4.617

–

–

Insoluble

KNO3

2.11

2 (Mohs)

(011)-p

Soluble

KPb2Cl5

4.78

2.5 (Mohs)

–

Insoluble

KTaB2O6

4.262

–

(001)-p

Insoluble

KTaO3

5.996 ?

–

–

Insoluble

KTi3NbO9

3.88

–

–

Insoluble

KTiNbO5

3.82

–

–

Insoluble

KTiOAsO4

3.454

–

None

Insoluble

KTiOPO4

3.024

702

None

Insoluble

KVO3

2.879

–

(010)-p

–

KY(MoO4)2

5.40

–

–

–

Biaxial

Density

Hardness

Cleavage

Solubility (ºC)

material

(g/cm3)

(kg/mm2)

plane

(g/100 g H2O)

KY(WO4)2

6.56

–

–

–

LaB3O6

4.216

–

(010)-p

–

La2(WO4)3

6.626

–

–

–

La2Ba3(BO3)4

5.353

–

–

–

La2Be2O5

6.061

900(100)

(010)-i

Insoluble

La2Ca3(BO3)4

4.157

–

–

–

La2O2SO4

5.467

–

–

–

La2SiO5

–

–

–

Insoluble

La2Sr3(BO3)4

4.783

–

–

–

La2Ti2O7

5.782

648

(010)-p

Insoluble

La2TiO5

5.5

–

–

Insoluble

La3NbO7

6.25

–

–

Insoluble

La3SbO7

6.558

–

–

Insoluble

La3TaO7

7.139

–

–

Insoluble

LaAlGe2O7

5.18

–

–

Insoluble

LaBMoO6

5.293

–

–

–

LaBO3

5.304

–

–

–

LaBWO6

6.185

–

–

–

LaGaGe2O7

–

–

–

Insoluble

LaGaO3

7.21

–

–

Insoluble

LaInO3

–

–

–

–

LaMgB5O10

3.923

–

–

–

LaNb5O15

6.264

–

–

Insoluble

LaNbO4

5.914

–

–

Insoluble

LaP5O14

3.290

–

–

Insoluble

LaPO4

5.067

5.5 (Mohs)

(100)-i

Insoluble

LaSbO4

6.30

–

–

Insoluble

LaScO3

5.79

–

–

Insoluble

LaVO4

–

–

–

Insoluble

LaY(WO4)3

6.53

–

–

–

Li2BeSiO4

2.69

7 (Mohs)

(010)-i

Insoluble

Li2CO3

2.097

–

–

Slightly soluble

Li2GeO3

3.489

–

–

Insoluble

Li2MgGeO4

3.31

–

–

Insoluble

Li2SiO3

2.527

–

–

Insoluble

Li3La2(BO3)3

4.50

–

–

–

Li3PO4

2.48

4 (Mohs)

(010)-p

Insoluble

Li3VO4

2.645

–

–

Insoluble

Li3Y2(BO3)3

3.50

–

–

–

Li5AlO4

2.251

–

–

–

Li6Al2(BO3)4

2.58

–

–

–

Li6Lu(BO3)3

3.538

–

–

–

Li6Y(BO3)3

2.76

–

–

–

Biaxial

Density

Hardness

Cleavage

Solubility (ºC)

material

(g/cm3)

(kg/mm2)

plane

(g/100 g H2O)

LiAl(MoO4)2

3.95

–

–

–

LiAl(PO4)F

3.10

5.5 (Mohs)

(100)(110)-p

Insoluble

LiAlGe2O6

4.354

–

–

Insoluble

LiAlSi2O6

3.1

7 (Mohs)

(010)-p

Insoluble

LiAlSi4O10

2.40

6.5 (Mohs)

(001)-p

Insoluble

LiBaAlF6

4.114

–

–

–

LiBaGaF6

4.526

–

–

–

LiBO2

2.883

–

–

–

LiB3O5

2.474

7 (Mohs)

None

Insoluble

LiGa(WO4)2

7.44

–

–

–

LiGaGe2O6

4.783

–

–

Insoluble

LiGaO2

4.175

–

–

Insoluble

LiGaSi2O6

–

–

–

Insoluble

LiGdO2

6.246

–

–

–

LiGdP4O12

–

–

–

Insoluble

LiIn(MoO4)2

4.149

–

–

–

LiIn(WO4)2

7.47

–

–

–

LiInGe2O6

5.041

–

–

Insoluble

LiInSi2O6

4.071

–

–

Insoluble

LiInSiO4

4.160

–

–

Insoluble

LiLa(MoO4)2

4.551

–

–

–

LiLaO2

6.18

–

–

Soluble

LiLaP4O12

–

–

–

Insoluble

LiLu(WO4)2

8.02

–

–

–

LiLuGeO4

5.98

–

–

Insoluble

LiLuP4O12

–

–

–

Insoluble

LiLuSiO4

5.46

–

–

Insoluble

LiSc(WO4)2

6.716

–

–

–

LiScGe2O6

4.157

–

–

Insoluble

LiScGeO4

3.928

–

–

Insoluble

LiScSi2O6

3.090

–

–

Insoluble

LiScSiO4

3.183

–

–

Insoluble

LiVO3

2.971

–

(100)-p

Insoluble

LiY(WO4)2

6.83

–

–

–

LiYGeO4

4.365

–

–

Insoluble

LiYO2

6.258

–

–

–

LiYSiO4

3.746

–

–

Insoluble

LiZnBO3

3.64

–

–

–

Lu2MoO6

8.167

–

–

–

Lu2O2SO4

7.854

–

–

–

Lu2SiO5

5.892

6.5 (Mohs)

None

Insoluble

Lu2WO6

9.718

–

–

–

LuCaBO4

6.036

–

–

–

Biaxial

Density

Hardness

Cleavage

Solubility (ºC)

material

(g/cm3)

(kg/mm2)

plane

(g/100 g H2O)

LuP5O14

3.72

–

–

Insoluble

LuTaO4

9.761

–

–

Insoluble

Mg2(PO4)F

3.15

5 (Mohs)

(100)-i

Insoluble

Mg2B2O5

2.910

5.5 (Mohs)

(hk0)-p

Insoluble

Mg2BO3F

2.784

–

–

Insoluble

Mg2GeO4

4.028

–

–

Insoluble

Mg2SiO4

3.22

7 (Mohs)

(010)-i

Insoluble

Mg3(PO4)2

2.76

–

(100)(010)

Insoluble

Mg3B2O6

3.04

6.5 (Mohs)

(110)-p

Insoluble

Mg3B7O13Cl

2.95

7 (Mohs)

None

Slightly soluble

Mg3TiB2O8

3.35

3.5 (Mohs)

(100)-p

Insoluble

Mg4Al8Si2O20

3.489

7.5 (Mohs)

(010)(001)-i

Insoluble

Mg4Ga8Ge2O20

–

–

–

Insoluble

Mg5(BO3)3F

3.112

–

–

Insoluble

MgAl3BSiO9

2.98

7.5 (Mohs)

(100)-p

Insoluble

MgAlBO4

3.45

7 (Mohs)

None

Insoluble

MgGaBO4

4.285

–

–

Insoluble

MgGeO3

4.282

–

–

Insoluble

MgMoO4

3.809

–

–

–

MgSiO3

3.21

5–6 (Mohs)

(110)-i

Insoluble

MgTi(SO4)3

2.82

–

–

–

MgTi2O5

3.649

–

–

Insoluble

MgWO4

6.893

–

–

–

Na(Sr,Ba)PO4

2.919

–

–

Insoluble

Na2BaTi2Si4O14

3.43

6 (Mohs)

(100)-i

Insoluble

Na2BeF4

2.482

–

–

–

Na2BeSi2O6

2.70

6 (Mohs)

(100)-i

Insoluble

Na2Ca(PO4)F

2.88

–

–

Insoluble

Na2CaMg(PO4)2

3.10

4.5 (Mohs)

–

Insoluble

Na2GeO3

3.319

–

–

Insoluble

Na2KTiNbSi4O14

2.968

6.5 (Mohs)

–

Insoluble

Na2LiAlF6

2.98

–

(001)-p

Slightly soluble

Na2LiYSi6O15

2.76

–

–

Insoluble

Na2MgAlF7

2.97

3.5 (Mohs)

(110)-i

Slightly soluble

Na2MgGaF7

3.359

–

–

–

Na2MgInF7

3.627

–

–

–

Na2MgScF7

2.853

–

–

–

Na2MgSiO4

2.75

–

–

Insoluble

Na2Si2O5

–

–

(100)-p

Slightly soluble

Na2SiO3

2.64

–

–

Insoluble

Na2Ti2Si2O9

3.44

6 (Mohs)

(010)-i

Insoluble

Na2ZnCl4

2.382

–

–

–

Na3AlF6

2.90

2.5 (Mohs)

(001)-p

Slightly soluble

Biaxial

Density

Hardness

Cleavage

Solubility (ºC)

material

(g/cm3)

(kg/mm2)

plane

(g/100 g H2O)

Na3GdSi3O9

3.439

–

–

Insoluble

Na3La(BO3)2

3.49

–

–

–

Na3La2(BO3)3

4.19

–

–

–

Na3ScSi2O7

2.861

–

–

Insoluble

Na3YSi3O9

2.962

–

–

Insoluble

NaAl(AsO4)F

3.64

5 (Mohs)

(110)-i

Slightly soluble

NaAl(PO4)F

3.126

4.5 (Mohs)

(111)-i

Insoluble

NaAlGeO4

3.337

–

(010)-p

Insoluble

NaAlSi3O8

2.63

6–6.5 (Mohs)

(001)-p

Insoluble

NaBePO4

2.81

5.5 (Mohs)

(010)-p

Insoluble

NaBF4

2.53

3 (Mohs)

(100)(010)

Soluble

NaCaPO4

3.117

3 (Mohs)

–

–

NaCdPO4

4.10

–

–

–

NaGaGe2O6

4.864

–

–

Insoluble

NaGaGeO4

4.028

–

(010)-p

Insoluble

NaGaSiO4

3.336

–

(010)-p

Insoluble

NaGdGeO4

5.366

–

–

Insoluble

NaGdP2O7

4.287

–

–

Insoluble

NaGdP4O12

3.45

–

–

Insoluble

NaGdSiO4

–

–

–

Insoluble

NaIn(MoO4)2

4.02

–

–

–

NaLaP2O7

3.803

–

–

Insoluble

NaLaP4O12

3.4

–

–

Insoluble

NaLiV2O6

2.962

–

–

–

NaLuGeO4

6.025

–

–

Insoluble

NaLuP2O7

4.114

–

–

Insoluble

NaLuSiO4

5.435

–

–

Insoluble

NaMgF3

3.06

–

–

–

NaNbO3

4.57

5.5 (Mohs)

–

Insoluble

NaScGeO4

3.39

–

–

Insoluble

NaScSi2O6

3.22

–

–

Insoluble

NaSr3Al3F16

3.51

4 (Mohs)

None

Slightly soluble

NaTaO3

7.123

–

–

Insoluble

NaVO3

2.91

–

(110)-p

0.8

NaYGeO4

4.302

–

–

Insoluble

NaYO2

4.382

–

–

Slightly soluble

NaYSiO4

4.083

–

–

Insoluble

NaZnF3

4.105

–

–

–

NH4B5O8•4H2O

1.57

2.5 (Mohs)

(100)-p

–

Pb2KNb5O15

6.143

–

(001)

Insoluble

Pb2NaNb5O15

–

–

–

Insoluble

Pb2V2O7

6.46

3 (Mohs)

–

-

Pb3(PO4)2

7.456

–

–

–

Biaxial

Density

Hardness

Cleavage

Solubility (ºC)

material

(g/cm3)

(kg/mm2)

plane

(g/100 g H2O)

Pb3(VO4)2

7.44

–

–

–

Pb3GeO5

–

–

–

Insoluble

Pb3MgNb2O9

–

–

–

Insoluble

Pb3ZnNb2O9

–

–

–

Insoluble

PbBi2Nb2O9

6.684

–

–

Insoluble

PbBr2

6.693

–

(001)-p

–

PbCl2

5.85

31

(001)-p

0.99 (20)

PbCO3

6.55

3 (Mohs)

(110)(021)-i

Very slightly soluble

PbGeO3

6.968

–

–

Insoluble

PbO (massicot)

9.642

(100)-p

–

PbNb2O6

–

–

–

Insoluble

PbSeO3

7.12

3.5 (Mohs)

(001)-p

–

PbSeO4

7.08

3.5 (Mohs)

None

–

PbSiO3

6.32

4.5 (Mohs)

(010)-p

Insoluble

PbSO4

6.32

3.5 (Mohs)

(001)(210)

Insoluble

PbTa2O6

7.65

–

–

Insoluble

PbTiP2O8

–

–

–

Insoluble

PbZnSiO4

6.13

3 (Mohs)

(120)-i

Insoluble

RbAlSiO4

–

–

–

Insoluble

RbB5O8•4H2O

1.946

2.5 (Mohs)

–

–

Rb2BeF4

3.749

–

–

–

RbBi(MoO4)2

5.52

–

–

–

RbGd2Br7

4.79

–

–

Slightly soluble

RbLa(WO4)2

6.88

–

–

–

RbNbB2O6

3.584

–

(001)-p

Insoluble

RbTaB2O6

4.65

–

(001)-p

Insoluble

RbTiOAsO4

4.018

–

None

Insoluble

RbTiOPO4

3.647

–

None

Insoluble

Sb2O3

5.83

2.5–3 (Mohs)

(110)-p

Insoluble

SbNbO4

5.68

5.5 (Mohs)

(010)-i

Insoluble

SbTaO4

7.53

5–5.5 (Mohs)

(010)-i

Insoluble

Sc(PO3)3

2.736

–

–

Insoluble

Sc2(MoO4)3

3.102

–

–

–

Sc2(WO4)3

4.566

–

(010)-p

Slightly soluble

Sc2Si2O7

–

–

–

Insoluble

(Sc,Y)2Si2O7

3.39

6.5 (Mohs)

(110)-i

Insoluble

Sc2SiO5

3.49

–

–

Insoluble

Sc2TiO5

3.611

–

–

Insoluble

ScAlBeO4

–

–

None

Insoluble

ScCaBO4

3.319

–

–

–

ScGaO3

5.10

–

(010)-p

Insoluble

ScGe2O5

5.286

–

–

Insoluble

ScMgBO4

3.287

–

–

–

Biaxial

Density

Hardness

Cleavage

Solubility (ºC)

material

(g/cm3)

(kg/mm2)

plane

(g/100 g H2O)

ScNbO4

4.843

–

(010)-p

Insoluble

ScTaO4

6.90

–

(010)-p

Insoluble

Sr2(AsO4)Cl

–

–

(010)-p

–

Sr2(VO4)Br

4.342

–

–

–

Sr2(VO4)Cl

3.883

–

(010)-p

–

Sr2KNb5O15

–

–

–

Insoluble

Sr2KTa5O15

–

–

–

Insoluble

Sr2NaNb5O15

5.19

–

–

Insoluble

Sr2Nb2O7

5.204

–

–

Insoluble

Sr2Ta2O7

7.074

–

–

Insoluble

SrAl2Ge2O8

3.714

–

–

Insoluble

SrAl2O4

3.554

–

–

–

SrAl2Si2O8

3.13

–

–

Insoluble

SrAl4O7

3.266

–

–

–

SrB2O4

3.350

–

–

–

SrCO3

3.79

3.5 (Mohs)

(010)-i

Very slightly soluble

SrGa2O4

4.85

–

–

–

SrGa2Si2O8

3.797

–

–

Insoluble

SrGd2O4

7.287

–

–

Insoluble

SrIn2O4

6.854

–

–

–

SrLu2O4

8.496

–

–

Insoluble

SrNb2O6

–

–

–

Insoluble

SrSc2O4

–

–

–

Insoluble

SrSiO3

3.66

–

–

Insoluble

SrSO4

3.97

3 (Mohs)

(001)-p

Insoluble

SrTa2O6

–

–

–

Insoluble

SrY2O4

5.344

–

–

–

SrZnGe2O6

–

–

–

Insoluble

TeO2

6.00

2 (Mohs)

(010)-p

Very slightly soluble

TlNbB2O6

–

–

(001)-p

Insoluble

TlTaB2O6

–

–

(001)-p

Insoluble

V2O5

3.37

–

–

–

Y2(MoO4)3

3.3

–

–

Very soluble

Y2(WO4)3

–

–

(010)-p

Very soluble

Y2BeO4

4.582

–

–

Insoluble

Y2GdSbO7

6.443

–

–

Insoluble

Y2GdTaO7

7.102

–

–

Insoluble

Y2GeO5

–

–

–

Insoluble

Y2MgBe2Si2O10

4.152

6.5 (Mohs)

None

Insoluble

Y2MoO6

5.366

–

–

–

Y2O2SO4

4.813

–

–

–

Y2Si2O7

4.3

6 (Mohs)

None

Insoluble

Y2SiO5

4.543

6.5 (Mohs)

None

Insoluble

Biaxial

Density

Hardness

Cleavage

Solubility (ºC)

material

(g/cm3)

(kg/mm2)

plane

(g/100 g H2O)

Y2Ti2SiO9

–

–

–

Insoluble

Y2WO6

6.818

–

–

–

Y3SbO7

5.699

–

–

Insoluble

Y3TaO7

6.413

–

–

Insoluble

Y4Al2O9

4.518

–

–

Insoluble

YAlO3

5.35

1030–1450

(110)-p

Insoluble

YCa4O(BO3)3

–

6–6.5 (Mohs)

None

Insoluble

YCaGaBe2Si2O10

4.107

6.5 (Mohs)

None

Insoluble

YF3

5.056

–

–

–

YGd2Nb2O9

6.802

–

–

Insoluble

YHfTaO6

8.13

–

–

Insoluble

YNbO4

5.58

–

–

Insoluble

YP5O14

–

–

–

Insoluble

YScO3

4.94

–

–

Insoluble

YTaO4

7.579

–

–

Insoluble

YTiTaO6

6.51

–

–

Insoluble

Zn3(AsO3)2

4.27

5 (Mohs)

(110)-i

Insoluble

Zn3(BO3)2

4.12

–

–

–

ZnB4O7

3.07

–

–

–

ZnWO4

7.87

–

–

–

ZrO2

5.82

6.5 (Mohs)

(001)-p

Insoluble