| Gabrielite | Tl₂AgCu₂As₃S₇ | Triclinic | — | — |
| Gabrielsonite | PbFe³⁺(As³⁺O₃)O | — | — | — |
| Gadolinite-(Ce) | Ce₂Fe²⁺Be₂Si₂O₁₀ | Monoclinic | — | — |
| Gadolinite-(Nd) | Nd₂Fe²⁺Be₂O₂(SiO₄)₂ | Monoclinic | — | — |
| Gadolinite-(Y) | Y₂Fe²⁺Be₂Si₂O₁₀ | Monoclinic | — | — |
| Gagarinite-(Ce) | NaCaCeF₆ | Trigonal | — | — |
| Gagarinite-(Y) | NaCaYF₆ | Hexagonal | — | — |
| Gageite | — | — | — | — |
| Gahnite | ZnAl₂O₄ | Cubic | — | 4.63 g/cm³ |
| Gaidonnayite | Na₂Zr(Si₃O₉)·2H₂O | — | — | — |
| Gaildunningite | Hg²⁺₃[NHg²⁺₂]₁₈(Cl,I,OH,Br,S)₂₄ | Orthorhombic | — | — |
| Gainesite | Na₂(Be,Li)Zr₂(PO₄)₄·1.5H₂O | — | — | — |
| Gaitite | Ca₂Zn(AsO₄)₂·2H₂O | — | — | — |
| Gajardoite | KCa₀.₅As³⁺₄O₆Cl₂(H₂O)₃·2H₂O | Hexagonal | — | — |
| Gajardoite-(NH₄) | (NH₄)As³⁺₄O₆Cl₂(Ca₀,₅◻₀,₅)(H₂O)₅ | Hexagonal | — | — |
| Galaxite | Mn²⁺Al₂O₄ | Cubic | 7.5 | — |
| Galeaclolusite | Al₆(AsO₄)₃(OH)₉(H₂O)₄·8H₂O | Orthorhombic | — | 2.27 g/cm³ |
| Galeite | Na₁₅(SO₄)₅F₄Cl | Trigonal | — | — |
| Galena | PbS | Cubic | 2.8 | 7.50 g/cm³ |
| Galenobismutite | PbBi₂S₄ | Orthorhombic | — | 7.04 g/cm³ |
| Galgenbergite-(Ce) | CaCe₂(CO₃)₄·H₂O | Triclinic | — | — |
| Galileiite | NaFe²⁺₄(PO₄)₃ | Trigonal | — | — |
| Galkhaite | (Hg₅Cu)CsAs₄S₁₂ | — | — | — |
| Galliskiite | Ca₄Al₂(PO₄)₂F₈·5H₂O | Triclinic | — | — |
| Gallite | CuGaS₂ | Tetragonal | — | 4.41 g/cm³ |
| Gallobeudantite | PbGa₃(AsO₄)(SO₄)(OH)₆ | Trigonal | 4.0 | 4.61 g/cm³ |
| Galloplumbogummite | Pb(Ga,Al,Ge)₃(PO₄)₂(OH)₆ | Trigonal | — | 4.62 g/cm³ |
| Galuskinite | Ca₇(SiO₄)₃(CO₃) | Monoclinic | — | — |
| Gamagarite | Ba₂Fe³⁺(VO₄)₂(OH) | — | — | — |
| Gananite | BiF₃ | Cubic | — | 8.17 g/cm³ |
| Ganomalite | Pb₉Ca₅Mn(Si₂O₇)₄(SiO₄)O | Hexagonal | — | — |
| Ganophyllite | (K,Na,Ca)₂Mn₈(Si,Al)₁₂(O,OH)₃₂·8H₂O | — | — | — |
| Ganterite | (Ba,Na,K)(Al,Mg)₂(AlSi₃O₁₀)(OH)₂ | — | — | — |
| Gaotaiite | Ir₃Te₈ | Cubic | — | — |
| Garavellite | FeSbBiS₄ | Orthorhombic | — | — |
| Garmite | CsLiMg₂(Si₄O₁₀)F₂ | Monoclinic | — | — |
| Garrelsite | Ba₃NaSi₂B₇O₁₆(OH)₄ | Monoclinic | — | — |
| Garronite-Ca | Ca₃(Al₆Si₁₀O₃₂)·14H₂O | Tetragonal | — | — |
| Garronite-Na | Na₆(Al₆Si₁₀O₃₂)·8.5H₂O | Monoclinic | — | — |
| Gartrellite | PbCuFe³⁺(AsO₄)₂(OH)·H₂O | — | 4.5 | — |
| Garutiite | (Ni,Fe,Ir) | Hexagonal | 6.0 | — |
| Garyansellite | (Mg,Fe)₃(PO₄)₂(OH,O) * 1.₅H₂O | Orthorhombic | — | — |
| Gasparite-(Ce) | Ce(AsO₄) | Monoclinic | — | — |
| Gasparite-(La) | La(AsO₄) | Monoclinic | — | 5.53 g/cm³ |
| Gaspéite | NiCO₃ | Trigonal | — | 4.43 g/cm³ |
| Gatedalite | ZrMn²⁺₂Mn³⁺₄O₈(SiO₄) | Tetragonal | — | — |
| Gatehouseite | Mn²⁺₅(PO₄)₂(OH)₄ | — | — | — |
| Gatelite-(Ce) | CaCe₃Al₂(Al,Mg)(Mg,Fe²⁺,Al)(Si₂O₇)(SiO₄)₃(O,F)(OH,O)₂ | Monoclinic | — | — |
| Gatewayite | Ca₆(H₂O)23(As³⁺V⁴⁺₃V⁵⁺₉As⁵⁺₆O₅₁)·8H₂O | Monoclinic | 2.0 | — |
| Gatumbaite | CaAl₂(PO₄)₂(OH)₂·H₂O | Monoclinic | — | — |
| Gaudefroyite | — | Hexagonal | 6.0 | — |
| Gaultite | Na₄Zn₂Si₇O₁₈·5H₂O | Orthorhombic | — | — |
| Gauthierite | KPb[(UO₂)₇O₅(OH)₇]·8H₂O | Monoclinic | — | 5.44 g/cm³ |
| Gayite | NaMnFe₅(PO₄)₄(OH)₆·2H₂O | Monoclinic | — | — |
| Gaylussite | Na₂Ca(CO₃)₂·5H₂O | Monoclinic | — | 2.00 g/cm³ |
| Gazeevite | BaCa₆(SiO₄)₂(SO₄)₂O | Trigonal | — | — |
| Gearksutite | CaAlF₄(OH)·H₂O | Triclinic | — | — |
| Gebhardite | Pb₈(As₂O₅)₂OCl₆ | Monoclinic | — | — |
| Gedrite | ☐Mg₂Mg₃Al₂(Si₆Al₂)O₂₂(OH)₂ | Orthorhombic | — | — |
| Geerite | Cu₈S₅ | Trigonal | — | — |
| Geffroyite | (Cu,Fe,Ag)₉(Se,S)₈ | Cubic | — | — |
| Gehlenite | Ca₂Al(SiAl)O₇ | Tetragonal | — | — |
| Geigerite | Mn²⁺₅(AsO₄)₂(HAsO₄)₂·10H₂O | — | — | — |
| Geikielite | MgTiO₃ | Trigonal | — | 3.89 g/cm³ |
| Gelosaite | BiMo⁶⁺₂₋₅ₓMo⁵⁺₆ₓO₇(OH)·H₂O (0 < x < 0.4) | Monoclinic | — | — |
| Geminite | Cu(HAsO₄)·H₂O | Triclinic | — | — |
| Gengenbachite | KFe₃(H₂PO₄)₂(HPO₄)₄·6H₂O | Hexagonal | — | — |
| Genkinite | Pt₄Sb₃ | Tetragonal | — | — |
| Genplesite | Ca₃Sn(SO₄)₂(OH)₆·3H₂O | Hexagonal | — | — |
| Genthelvite | Be₃Zn₄(SiO₄)₃S | Cubic | — | 3.60 g/cm³ |
| Geocronite | Pb₁₄(Sb,As)₆S₂₃ | Monoclinic | 2.5 | — |
| Georgbarsanovite | Na₁₂(Mn,Sr,REE)₃Ca₆Fe²⁺₃Zr₃NbSi₂₅O₇₆Cl₂·H₂O | Trigonal | — | — |
| Georgbokiite | Cu₅(SeO₃)₂O₂Cl₂ | Monoclinic | — | — |
| George-ericksenite | Na₆CaMg(IO₃)₆(CrO₄)₂·12H₂O | Monoclinic | — | — |
| Georgechaoite | NaKZr[Si₃O₉]·2H₂O | — | — | — |
| Georgeite | Cu₂(CO₃)(OH)₂ | Amorphous | — | — |
| Georgeliuite | Ca₂Mn³⁺₃O₂(AsO₄)₃(H₂O)₂·H₂O | Monoclinic | — | — |
| Georgerobinsonite | Pb₄(CrO₄)₂(OH)₂FCl | Orthorhombic | — | — |
| Georgiadesite | Pb₄(As³⁺O₃)Cl₄(OH) | — | — | — |
| Gerasimovskite | Mn²⁺(Nb,Ti)₅O₁₂·9H₂O | Amorphous | — | — |
| Gerdtremmelite | (Zn,Fe)(Al,Fe)₂(AsO₄)(OH)₅ | Triclinic | — | — |
| Gerenite-(Y) | (Ca,Na)₂(Y,REE)₃Si₆O₁₈·2H₂O | Triclinic | — | — |
| Gerhardtite | Cu₂NO₃(OH)₃ | Orthorhombic | — | — |
| Germanite | Cu₁₃Fe₂Ge₂S₁₆ | Cubic | 3.0 | — |
| Germanocolusite | Cu₁₃VGe₃S₁₆ | — | — | — |
| Gersdorffite | NiAsS | Cubic | 5.5 | 5.90 g/cm³ |
| Gerstleyite | Na₂(Sb,As)₈S₁₃·2H₂O | Monoclinic | — | — |
| Gerstmannite | MnMgZn(SiO₄)(OH)₂ | Orthorhombic | — | — |
| Geschieberite | K₂(UO₂)(SO₄)₂·2H₂O | Orthorhombic | — | — |
| Getchellite | AsSbS₃ | Monoclinic | — | — |
| Geuerite | Ag₂Tl₄Pb₄As₂₂S₄₀ | Monoclinic | — | — |
| Geversite | PtSb₂ | Cubic | — | 10.61 g/cm³ |
| Ghiaraite | CaCl₂·4H₂O | Triclinic | — | — |
| Giacovazzoite | — | Monoclinic | — | — |
| Gianellaite | [(NHg₂)₂](SO₄)(H₂O)x | Cubic | — | — |
| Gibbsite | Al(OH)₃ | Monoclinic | — | — |
| Giessenite | (Cu,Fe)₂Pb₂₆.₄(Bi,Sb)₁₉.₆S₅₇ | Monoclinic | 2.5 | — |
| Giftgrubeite | CaMn₂Ca₂(AsO₄)₂(AsO₃OH)₂·4H₂O | Monoclinic | — | — |
| Gilalite | Cu₅Si₆O₁₇·7H₂O | Monoclinic | — | — |
| Gillardite | Cu₃Ni(OH)₆Cl₂ | Trigonal | — | — |
| Gillespite | BaFe²⁺Si₄O₁₀ | — | — | — |
| Gillulyite | Tl₂As₇.₅Sb₀.₃S₁₃ | — | — | — |
| Gilmarite | Cu²⁺₃(AsO₄)(OH)₃ | Triclinic | — | — |
| Ginelfite | Ag₂(Ag₀.₅Fe²⁺₀.₅)TlPb₂₃.₅(Sb,As)₃₃.₅S₇₆ | — | — | — |
| Giniite | Fe²⁺Fe³⁺₄(PO₄)₄(OH)₂·2H₂O | Monoclinic | — | — |
| Ginorite | Ca₂B₁₄O₂₀(OH)₆·5H₂O | Monoclinic | — | — |
| Giorgiosite | Mg₅(CO₃)₄(OH)₂·5H₂O | — | — | — |
| Giraudite-(Zn) | Cu₆(Cu₄Zn₂)As₄Se₁₃ | — | — | — |
| Girdite | — | Monoclinic | — | — |
| Girvasite | NaCa₂Mg₃(PO₄)₃(CO₃)(H₂O)₆ | Monoclinic | — | — |
| Gismondine-Ca | Ca₂(Si₄Al₄)O₁₆·8H₂O | Monoclinic | — | — |
| Gismondine-Sr | Sr₄(Si₈Al₈O₃₂)·9H₂O | Orthorhombic | — | — |
| Gittinsite | CaZrSi₂O₇ | Monoclinic | — | — |
| Giuseppettite | (Na,K,Ca)₇-₈(Al₆Si₆O₂₄)(SO₄,Cl)₁-₂ | Trigonal | — | — |
| Giuşcăite | Ag₂Tl₄Pb₄As₂₀Sb₂S₄₀ | Monoclinic | — | — |
| Gjerdingenite-Ca | K₂Ca(Nb,Ti)₄(Si₄O₁₂)₂(O,OH)₄·6H₂O | Monoclinic | — | — |
| Gjerdingenite-Fe | K₂Fe(Nb,Ti)₄(Si₄O₁₂)₂(O,OH)₄·6H₂O | — | — | — |
| Gjerdingenite-Mn | K₂Mn(Nb,Ti)₄(Si₄O₁₂)₂(O,OH)₄·6H₂O | — | — | — |
| Gjerdingenite-Na | K₂Na(Nb,Ti)₄(Si₄O₁₂)₂(OH,O)₄·5H₂O | Monoclinic | — | — |
| Gladite | CuPbBi₅S₉ | Orthorhombic | — | — |
| Gladiusite | — | Monoclinic | — | — |
| Gladkovskyite | MnTlAs₃S₆ | Trigonal | — | — |
| Glagolevite | Na(Mg,Al)₆(AlSi₃O₁₀)(OH,O)₈ | — | — | — |
| Glauberite | Na₂Ca(SO₄)₂ | Monoclinic | — | 2.84 g/cm³ |
| Glaucocerinite | (Zn₁-xAlx)(OH)₂(SO₄)x/₂ * nH₂O | Hexagonal | 1.0 | — |
| Glaucochroite | CaMn²⁺(SiO₄) | Orthorhombic | 6.0 | — |
| Glaucodot | (Co₀.₅Fe₀.₅)AsS | Orthorhombic | 5.0 | 6.06 g/cm³ |
| Glaucophane | ☐Na₂(Mg₃Al₂)Si₈O₂₂(OH)₂ | Monoclinic | 6.0 | — |
| Glaukosphaerite | CuNi(CO₃)(OH)₂ | Monoclinic | 3.5 | — |
| Glecklerite | Na(C₂H₃O₃) | Orthorhombic | — | — |
| Glikinite | Zn₃O(SO₄)₂ | Monoclinic | — | 3.90 g/cm³ |
| Glucine | CaBe₄(PO₄)₂(OH)₄·0.5H₂O | — | — | — |
| Glushinskite | Mg(C₂O₄)·2H₂O | Monoclinic | 2.0 | 1.85 g/cm³ |
| Gmalimite | K₆◻Fe²⁺₂₄S₂₇ | Cubic | — | — |
| Gmelinite-Ca | Ca₂(Si₈Al₄)O₂₄·11H₂O | Hexagonal | — | — |
| Gmelinite-K | K₄(Si₈Al₄)O₂₄·11H₂O | Hexagonal | — | — |
| Gmelinite-Na | Na₄(Si₈Al₄)O₂₄·11H₂O | Hexagonal | — | — |
| Gobbinsite | Na₅(Si₁₁Al₅)O₃₂·11H₂O | Orthorhombic | — | — |
| Gobelinite | — | Triclinic | — | — |
| Godlevskite | (Ni,Fe)₉S₈ | Orthorhombic | — | — |
| Godovikovite | (NH₄)Al(SO₄)₂ | Trigonal | — | — |
| Goedkenite | Sr₂Al(PO₄)₂(OH) | — | — | — |
| Goethite | FeO(OH) | Orthorhombic | — | 4.24 g/cm³ |
| Goldfieldite | (Cu₄☐₂)Cu₆Te₄S₁₃ | — | — | — |
| Goldhillite | Cu₅Zn(AsO₄)₂(OH)₆·H₂O | Monoclinic | — | — |
| Goldichite | KFe(SO₄)₂·4H₂O | Monoclinic | — | — |
| Goldmanite | Ca₃V³⁺₂(SiO₄)₃ | Cubic | — | — |
| Goldquarryite | — | Triclinic | — | — |
| Goldschmidtite | KNbO₃ | Cubic | — | 4.50 g/cm³ |
| Golyshevite | Na₁₀Ca₉Zr₃Fe₂SiNb(Si₃O₉)₂(Si₉O₂₇)₂(OH)₃(CO₃)·H₂O | Trigonal | — | — |
| Gonnardite | (Na,Ca)₂(Si,Al)₅O₁₀·3H₂O | Tetragonal | 5.0 | — |
| Gonyerite | (Mn²⁺,Mg)₅Fe³⁺(Fe³⁺Si₃O₁₀)(OH)₈ | — | — | — |
| Goosecreekite | Ca(Si₆Al₂)O₁₆·5H₂O | Monoclinic | — | — |
| Gorbunovite | CsLi₂(Ti,Fe)Si₄O₁₀(F,OH,O)₂ | Monoclinic | — | — |
| Gorceixite | BaAl₃(PO₄)(PO₃OH)(OH)₆ | Monoclinic | — | — |
| Gordaite | NaZn₄(SO₄)(OH)₆Cl·6H₂O | Trigonal | — | — |
| Gordonite | MgAl₂(PO₄)₂(OH)₂·8H₂O | — | — | — |
| Gorerite | — | Hexagonal | — | — |
| Gormanite | (Fe²⁺,Mg)₃(Al,Fe³⁺)₄(PO₄)₄(OH)₆ * 2H₂O | — | — | — |
| Gortdrumite | — | Orthorhombic | — | — |
| Goryainovite | Ca₂(PO₄)Cl | Orthorhombic | — | — |
| Goslarite | Zn(SO₄)·7H₂O | Orthorhombic | — | — |
| Gottardiite | Na₃Mg₃Ca₅Al₁₉Si₁₁₇O₂₇₂·93H₂O | Orthorhombic | — | — |
| Gottlobite | CaMg(VO₄)OH | Orthorhombic | 4.5 | — |
| Goudeyite | — | Hexagonal | — | — |
| Gowerite | Ca[B₅O₈(OH)][B(OH)₃]·3H₂O | Monoclinic | — | — |
| Goyazite | SrAl₃(PO₄)(PO₃OH)(OH)₆ | Trigonal | — | — |
| Graemite | — | — | — | — |
| Graeserite | Fe³⁺₄Ti₃As³⁺O₁₃(OH) | — | — | — |
| Graftonite | Fe²⁺Fe²⁺₂(PO₄)₂ | Monoclinic | — | — |
| Graftonite-(Ca) | CaFe²⁺₂(PO₄)₂ | Monoclinic | — | — |
| Graftonite-(Mn) | MnFe²⁺₂(PO₄)₂ | Monoclinic | — | — |
| Grahampearsonite | Ca₂P₂O₇ | Tetragonal | — | 2.95 g/cm³ |
| Gramaccioliite-(Y) | (Pb,Sr)(Y,Mn)Fe³⁺₂(Ti,Fe³⁺)₁₈O₃₈ | — | — | — |
| Grammatikopoulosite | — | Orthorhombic | — | — |
| Grandaite | Sr₂Al(AsO₄)₂(OH) | Monoclinic | — | — |
| Grandidierite | (Mg,Fe²⁺)(Al,Fe³⁺)₃(SiO₄)(BO₃)O₂ | Orthorhombic | — | — |
| Grandreefite | Pb₂(SO₄)F₂ | Monoclinic | — | 6.69 g/cm³ |
| Grandviewite | Cu₃Al₂(SO₄)(OH)₁₀·H₂O | Monoclinic | — | — |
| Grantsite | (Na,Ca)²⁺x(V₅+,V₄+)₆O₁₆ * 4H₂O | Monoclinic | — | — |
| Graphite | C | Hexagonal | 1.5 | 2.16 g/cm³ |
| Gratonite | Pb₉As₄S₁₅ | Trigonal | 2.5 | — |
| Grattarolaite | — | Trigonal | — | — |
| Graulichite-(Ce) | CeFe³⁺₃(AsO₄)₂(OH)₆ | — | — | — |
| Graulichite-(La) | LaFe³⁺₃(AsO₄)₂(OH)₆ | Trigonal | — | — |
| Gravegliaite | — | — | — | — |
| Grayite | (Th,Pb,Ca)(PO₄)·H₂O | Hexagonal | — | — |
| Graţianite | MnBi₂S₄ | Monoclinic | — | — |
| Grechishchevite | — | Tetragonal | — | — |
| Greenalite | (Fe²⁺,Fe³⁺)₂-₃Si₂O₅(OH)₄ | Monoclinic | — | — |
| Greenlizardite | (NH₄)Na(UO₂)₂(SO₄)₂(OH)₂·4H₂O | Triclinic | — | — |
| Greenockite | CdS | Hexagonal | — | 4.70 g/cm³ |
| Greenwoodite | Ba₂₋ₓ(V³⁺OH)ₓV³⁺₉(Fe³⁺,Fe²⁺)₂Si₂O₂₂ | Trigonal | — | — |
| Gregoryite | Na₂(CO₃) | Hexagonal | 3.0 | 2.65 g/cm³ |
| Greifensteinite | — | — | 4.5 | — |
| Greigite | Fe²⁺Fe³⁺₂S₄ | Cubic | — | 4.05 g/cm³ |
| Grenmarite | Na₂Zr₂Na₂MnZr(Si₂O₇)₂O₂F₂ | Monoclinic | — | — |
| Grguricite | — | Triclinic | — | — |
| Griceite | LiF | Cubic | — | 2.53 g/cm³ |
| Griffinite | Al₂TiO₅ | Orthorhombic | — | — |
| Grigorievite | Cu₃Fe³⁺₂Al₂(VO₄)₆ | Triclinic | — | — |
| Grimaldiite | CrO(OH) | — | — | 4.05 g/cm³ |
| Grimmite | — | Cubic | — | — |
| Grimselite | K₃Na(UO₂)(CO₃)₃·H₂O | Hexagonal | — | — |
| Griphite | Na₄Li₂Ca₆(Mn²⁺,Fe²⁺,Mg)₁₉Al₈(PO₄)₂₄(F,OH)₈ | — | — | — |
| Grischunite | NaCa₂Mn²⁺₅Fe³⁺(AsO₄)₆·2H₂O | Orthorhombic | — | — |
| Gritsenkoite | CoMg₂(AsO₄)₂(H₂O)₈ | Monoclinic | — | — |
| Groatite | ☐NaCaMn₂(PO₄)(HPO₄)₂ | Monoclinic | — | — |
| Grokhovskyite | — | Trigonal | — | — |
| Grootfonteinite | Pb₃O(CO₃)₂ | Hexagonal | — | — |
| Grossite | CaAl₄O₇ | Monoclinic | — | 2.90 g/cm³ |
| Grossmanite | Ca(Ti³⁺,Mg,Ti⁴⁺)AlSiO₆ | Monoclinic | — | — |
| Grossular | Ca₃Al₂(SiO₄)₃ | Cubic | — | — |
| Groutite | Mn³⁺O(OH) | — | — | 4.14 g/cm³ |
| Grumantite | NaSi₂O₄(OH)·H₂O | Orthorhombic | — | — |
| Grumiplucite | HgBi₂S₄ | Monoclinic | — | 6.77 g/cm³ |
| Grundmannite | CuBiSe₂ | Orthorhombic | — | — |
| Grunerite | ☐Fe²⁺₂Fe²⁺₅Si₈O₂₂(OH)₂ | Monoclinic | — | — |
| Gruzdevite | Cu₆Hg₃Sb₄S₁₂ | Trigonal | — | 5.53 g/cm³ |
| Guanacoite | Cu₂Mg₃(OH)₄(AsO₄)₂·4H₂O | Monoclinic | 3.0 | — |
| Guanajuatite | Bi₂Se₃ | — | — | 7.16 g/cm³ |
| Guangyuanite | Pb₃Cl₃(Se⁴⁺O₃)(OH) | Orthorhombic | — | — |
| Guarinoite | Zn₆(SO₄)(OH)₁₀·5H₂O | Hexagonal | — | — |
| Guastoniite-(Y) | Pb₄(YCa)(Si₈B₄O₂₈)F | Triclinic | — | — |
| Gudmundite | FeSbS | Monoclinic | — | 7.07 g/cm³ |
| Guettardite | PbAsSbS₄ | Monoclinic | — | — |
| Gugiaite | Ca₂Be(Si₂O₇) | Tetragonal | — | — |
| Guidottiite | MnFe³⁺₂(SiFe³⁺)O₅(OH)₄ | Hexagonal | — | — |
| Guildite | CuFe³⁺(SO₄)₂(OH)·4H₂O | Monoclinic | — | — |
| Guilleminite | Ba(UO₂)₃(Se⁴⁺O₃)₂O₂·3H₂O | Orthorhombic | 2.0 | — |
| Guimarãesite | Ca₂Be₄Zn₅(PO₄)₆(OH)₄·6H₂O | Monoclinic | — | — |
| Guite | Co²⁺Co³⁺₂O₄ | Cubic | — | — |
| Guixiangite | NiBiS | Cubic | — | — |
| Gungerite | TlAs₅Sb₄S₁₃ | Orthorhombic | — | — |
| Gunmaite | (Na₂Sr)Sr₂Al₁₀(PO₄)₄F₁₄(OH)₁₂ | — | — | — |
| Gunningite | Zn(SO₄)(H₂O) | Monoclinic | — | — |
| Gunterite | Na₄Ca(V₁₀O₂₈)·20H₂O | Monoclinic | — | — |
| Gupeiite | Fe₃Si | Cubic | — | — |
| Gurimite | Ba₃(VO₄)₂ | Trigonal | — | 5.09 g/cm³ |
| Gustavite | AgPbBi₃S₆ | Orthorhombic | — | — |
| Gutkovaite-Mn | CaK₂Mn(Ti,Nb)₄(Si₄O₁₂)₂(O,OH)₄·5H₂O | — | — | — |
| Guyanaite | CrO(OH) | — | — | 4.05 g/cm³ |
| Guérinite | Ca₅(AsO₃OH)₂(AsO₄)₂·9H₂O | — | 1.5 | — |
| Gwihabaite | (NH₄)(NO₃) | Orthorhombic | — | — |
| Gypsum | CaSO₄·2H₂O | Monoclinic | 2.0 | 2.32 g/cm³ |
| Gyrolite | NaCa₁₆(Si₂₃Al)O₆₀(OH)₈·14H₂O | — | — | — |
| Gysinite-(Ce) | PbCe(CO₃)₂(OH)(H₂O) | Orthorhombic | — | — |
| Gysinite-(Nd) | PbNd(CO₃)₂(OH)·H₂O | Orthorhombic | — | — |
| Görgeyite | K₂Ca₅(SO₄)₆·H₂O | Monoclinic | — | — |
| Götzenite | Ca₄NaCa₂Ti(Si₂O₇)₂(OF)F₂ | Triclinic | — | — |
| Günterblassite | (K,Ca,Ba,Na,☐)₃Fe[(Si,Al)₁₃O₂₅(OH,O)₄]·7H₂O | Orthorhombic | 4.0 | — |