MINERALMINERAL((DipersiapkanDipersiapkan sebagaisebagai materimateri kuliahkuliah Geologi Geologi DasarDasar didi

Program Program StudiStudi GeofisikaGeofisika, FMIPA, FMIPA--UGM)UGM)

OlehOleh::GAYATRI INDAH MARLIYANIGAYATRI INDAH MARLIYANI

SALAHUDDIN HUSEINSALAHUDDIN HUSEIN

Mineral Mineral dandan batuanbatuanPenyusunPenyusun kerakkerak bumibumi : : batuanbatuanPenyusunPenyusun batuanbatuan : mineral: mineralPembentukPembentuk mineral : atommineral : atom--atom atom atauatau molekulmolekul

BatuanBatuan dandan mineral : mineral : terbentukterbentuk oleholeh prosesproses alamalam

BerdasarkanBerdasarkan asalnyaasalnya, mineral , mineral dapatdapat dibedakandibedakan menjadimenjadi ::

1.1. Mineral primer : Mineral primer : hasilhasil daridari pembekuanpembekuan langsunglangsungmagma, magma, kristalisasikristalisasi daridari suatusuatu larutanlarutan kimiakimia, , atauatauprosesproses rekristalisasirekristalisasi dalamdalam bentukbentuk padatpadat padapada prosesprosesmetamorfismemetamorfisme, , terbagiterbagi menjadimenjadi: :

a.a. MagmatikMagmatik : : jikajika mineral mineral terkristalisasiterkristalisasi langsunglangsung daridari suatusuatu lelehanlelehanb.b. SedimenSedimen : : jikajika mineral mineral terkristalisasiterkristalisasi selamaselama prosesproses diagenesisdiagenesis

atauatau daridari larutanlarutan hidroksidahidroksida dibawahdibawah temperaturtemperatur normalnormalc.c. MetamorfikMetamorfik : : jikajika mineral mineral terkristalisasiterkristalisasi selamaselama prosesproses

metamorfosametamorfosa dalamdalam bentukbentuk padatpadat dandan rentangrentang suhusuhu dandan tekanantekananyang yang bervariasibervariasi ((termasuktermasuk metamorfismemetamorfisme regional regional dandan termaltermal))

d.d. HidrotermalHidrotermal : : jikajika mineral mineral terkristalisasiterkristalisasi daridari suatusuatu larutanlarutan dandancairancairan dibawahdibawah suhusuhu tinggitinggi hinggahingga rendahrendah

2.2. Mineral Mineral sekundersekunder: : hasilhasil prosesproses alterasialterasi daridari mineral mineral primer, primer, misalnyamisalnya prosesproses oksidasioksidasi atauatau reduksireduksi padapadasuhusuhu dandan temperaturtemperatur rendahrendah didi dekatdekat permukaanpermukaan, , terbagiterbagi menjadimenjadi ::

a.a. OksidasiOksidasi : : jikajika mineral mineral merupakanmerupakan hasilhasil daridari oksidasioksidasi ((pelapukanpelapukan) ) mineral primermineral primer

b.b. SementasiSementasi : : jikajika mineral mineral merupakanmerupakan hasilhasil daridari prosesproses reduksireduksimineral primermineral primer

PenggolonganPenggolongan mineralmineral

1.1. Native elements (Native elements (GolonganGolongan elemenelemen dasardasar))2.2. SulphidesSulphides ((GolonganGolongan SulfidaSulfida))3.3. Halides (Halides (GolonganGolongan HalidaHalida))4.4. Oxides (Oxides (GolonganGolongan OksidaOksida))5.5. Carbonates (Carbonates (GolonganGolongan KarbonatKarbonat))6.6. Borates (Borates (GolonganGolongan BoratBorat))7.7. SulphatesSulphates ((GolonganGolongan SulfatSulfat))8.8. PhospatesPhospates ((GolonganGolongan FosfatFosfat))9.9. Silicates (Silicates (GolonganGolongan SilikatSilikat))10.10. Organic compoundsOrganic compounds

Native ElementsNative Elements

Example :Example :-- Copper (Copper (tembagatembaga)) CuCu-- Silver (Silver (perakperak) ) AgAg-- Gold (Gold (emasemas) ) AuAu-- Iron ( Iron ( BesiBesi) ) FeFe-- Platinum (Platinum (platinaplatina) ) PtPt-- Graphite (Graphite (grafitgrafit) ) CC-- Sulfur (Sulfur (BelerangBelerang) ) SS-- Diamond (Diamond (IntanIntan) ) CC

CopperCopper

SilverSilver

Silver in calciteSilver in calcite

Ore GoldOre Gold

SulfurSulfur

PlatinumPlatinum

GrafitGrafitHexagonal Hexagonal

((rhombohedralrhombohedral) ) systemsystem

Diamond (Diamond (intanintan))OctahedralOctahedral

SulphidesSulphides

Example :Example :-- KalkopiritKalkopirit (CuFeS2)(CuFeS2)-- Galena (Galena (PbSPbS))-- Cinnabar (Cinnabar (HgSHgS))-- PiritPirit (FeS2)(FeS2)

PiritPirit

GalenaGalena

CinnabarCinnabar

HalidesHalides

Example :Example :-- Halite (Halite (garamgaram) ) NaClNaCl-- FluelliteFluellite-- CryolliteCryollite-- CreediteCreedite-- CarnalliteCarnallite-- BoleiteBoleite

HaliteHalite

FluelliteFluellite

OxidesOxides

Example :Example :-- CupriteCuprite (Cu2O)(Cu2O)-- AmethystAmethyst-- MagnetiteMagnetite-- ChromiteChromite-- MiniumMinium-- Corundum (Al2O3)Corundum (Al2O3)-- Hematite (Fe2O3)Hematite (Fe2O3)-- IlmeniteIlmenite (FeTiO3)(FeTiO3)-- Quartz (Quartz (KuarsaKuarsa) ) SiO2)SiO2)-- Opal (SiO2.nH20)Opal (SiO2.nH20)

CupriteCuprite

MagnetiteMagnetite

AmethystAmethyst

ChromiteChromite

CarbonatesCarbonates

Example :Example :-- MagnesiteMagnesite (MgCO3)(MgCO3)-- Siderite (FeCO3)Siderite (FeCO3)-- Calcite (Calcite (kalsitkalsit) ) CaCO3CaCO3-- Dolomites (CaMg(CO3)2)Dolomites (CaMg(CO3)2)-- Aragonite (CaCO3)Aragonite (CaCO3)-- AzuriteAzurite-- MalachiteMalachite

MagnesiteMagnesite

KalsitKalsit

DolomiteDolomite

AragonitAragonit dalamdalam dolomitdolomit

BoratesBorates

Example :Example :-- LudwigiteLudwigite-- InderiteInderite-- Borax (Na2B4O5(OH)4.8H2O)Borax (Na2B4O5(OH)4.8H2O)-- KerniteKernite (Na2B4O6(OH)2.3H2O)(Na2B4O6(OH)2.3H2O)-- BorsciteBorscite (Mg3B7O13Cl)(Mg3B7O13Cl)

LudwigiteLudwigite

BoraxBorax

InderiteInderite

SulfatesSulfates

Example : Example : -- Anglesite (PbSO4)Anglesite (PbSO4)-- Anhydrite (CaSO4)Anhydrite (CaSO4)-- Barite (BaSO4)Barite (BaSO4)-- Gypsum (CaSO4.2H2O)Gypsum (CaSO4.2H2O)-- Wulfenite (PbMoO4)Wulfenite (PbMoO4)

GypsumGypsum wulfenitewulfenite

AnhydriteAnhydrite

PhospatesPhospates

Example:Example:-- LithioposphateLithioposphate (Li3PO4)(Li3PO4)-- MimetiteMimetite (Pb5(AsO4)3Cl)(Pb5(AsO4)3Cl)-- CalchophyliteCalchophylite

(Cu18Al2(AsO4)3(SO4)3(OH)27.36H2O(Cu18Al2(AsO4)3(SO4)3(OH)27.36H2O

MimetitMimetit

SilicatesSilicates

Example :Example :-- PhenakitePhenakite (BeSiO4)(BeSiO4)-- Olivine (Mg,Fe)2SiO4Olivine (Mg,Fe)2SiO4-- Zircon (ZrSiO4)Zircon (ZrSiO4)-- SilimaniteSilimanite (Al2SiO5)(Al2SiO5)-- AndalusiteAndalusite (Al2SiO5)(Al2SiO5)-- KyaniteKyanite (Al2SiO5)(Al2SiO5)-- Topaz (Al2SiO4)Topaz (Al2SiO4)-- GolonganGolongan Mika (Mika (BiotitBiotit K(Fe,Mg)3AlSi3O10(OH,F)2)K(Fe,Mg)3AlSi3O10(OH,F)2)-- GolonganGolongan Feldspar(SanidineFeldspar(Sanidine KAlSi3O8, KAlSi3O8, OrthochlaseOrthochlase

KAlSi3O8, MicroclineKAlSi3O8, Microcline KAlSi3O8, AlbiteKAlSi3O8, Albite NaAlSi3O8, NaAlSi3O8, OligoclaseOligoclase, , dsbdsb))

Organic CompoundsOrganic Compounds

Example :Example :-- AmberAmber

IDENTIFIKASI MINERALIDENTIFIKASI MINERAL

FIELDFIELD pengamatanpengamatan langsunglangsung didi lapanganlapanganLABORATORYLABORATORY pengamatan/penyelidikanpengamatan/penyelidikan laboratoriumlaboratorium

FIELDFIELD

COLOR (COLOR (WarnaWarna):): LEAST RELIABLE IDENTIFYING LEAST RELIABLE IDENTIFYING CHARACTERISTICCHARACTERISTIC

LUSTER (LUSTER (kilapkilap):): DESCRIBES HOW A MINERALDESCRIBES HOW A MINERAL’’S SURFACE S SURFACE REFLECTS LIGHT ( VIBRATING ELECTRONS EMIT A DIFFUSE REFLECTS LIGHT ( VIBRATING ELECTRONS EMIT A DIFFUSE LIGHT, GIVING METALLIC SURFACES THEIR CHARACTERISTIC LIGHT, GIVING METALLIC SURFACES THEIR CHARACTERISTIC SHINY LUSTER) SHINY LUSTER)

STREAK (STREAK (ceratcerat) :) : COLOR OF A MINERAL IN ITS POWDERED FORM COLOR OF A MINERAL IN ITS POWDERED FORM –– OFTEN A MORE ACCURATE INDICATOR OF MINERAL OFTEN A MORE ACCURATE INDICATOR OF MINERAL IDENTITY.IDENTITY.

HARDNESS (kekerasan): MINERAL’S RESISTANCE TO SCRATCHING OR ABRASION – MINERAL’S HARDNESS INDICATES THE RELATIVE STRENGTH OF ITS BONDS

MOH’S HARDNESS SCALE: ASSIGNS RELATIVE HARDNESSES TO SEVERAL COMMON AND A FEW RARE AND PRECIOUS MINERALS

MOHMOH’’S HARDNESS SCALE:S HARDNESS SCALE:

((SkalaSkala kekerasankekerasan MohMoh’’ss))

10DIAMOND

9CORUNDUM

8TOPAZ

7QUARTZ

5APATITE

3CALCITE

2GYPSUM2

1TALC1

HARDNESSMINERAL

FINGER NAIL (kuku jari) 2.5

GLASS (kaca) 5-6

STEEL FILE (pisau baja) 6.5

Cara Cara mudahmudah untukuntuk menentukanmenentukankekerasankekerasan mineralmineral

CLEAVAGE (belahan): TENDENCY OF A MINERAL TO BREAK CONSISTENTLY ALONG DISTINCT PLANES IN THEIR CRYSTAL STRUCTURES WHERE THE BONDS ARE WEAKEST, OR FEWER IN NUMBERTWO MINERALS THAT ARE SIMILAR IN EXTERNAL FORM, HARDNESS AND OTHER CHARACTERISTICS MAY HAVE DIFFERENT CLEAVAGE PLANES

FRACTURE (pecahan): WHEN BONDS ARE EQUALLY STRONG IN ALL DIRECTIONS AND DISTRIBUTED UNIFORMLY MINERALS DO NOT CLEAVE – THEY FRACTURE AT RANDOMEXAMPLE: QUARTZ – ALL ATOMS BOND COVALENTLY

SMELL & TASTE (bau dan rasa) :HALITE SALTYKCl BITTERSULFUR CONTAINING MINERALS – H2S SMELL

EFFERVESCENCE (berbuih):CaCO3 + HCl ---------> EFFERVESCENCENaCl + HCl ---------> NO EFFERVESCENCE

CRYSTAL FORM (bentuk kristal): SHAPE OF A WELL FORMED CRYSTAL MAY BE DISTINCTIVE ENOUGH TO IDENTIFY THE MINERAL

SMELL & TASTESMELL & TASTE

TEST LABORATORIUM

SPECIFIC GRAVITY (berat jenis) =SUBSTANCE WEIGHT /WEIGHT OF EQUAL VOLUME OF H2O

DENSITY = MASS (G) / VOLUME (CM3)

POLYMORPHS HAVE SLIGHTLY DIFFERENT DENSITIESEX: GRAPHITE 2.3 while DIAMOND 3.5 (COMPRESSED CRYSTAL STRUCTURE)

TEST LABORATORIUM YANG LAIN :BY TRANSMITTED LIGHT THROUGH A THIN SECTION UNDER UV CERTAIN MINERALS GLOW –FLUORESCENCEPHOSPHORESCENCE – GLOW AFTER UV LIGHT IS REMOVED

ReferencesReferences

1.1. Handbook of Mineralogy by Anthony J.W Handbook of Mineralogy by Anthony J.W et alet al

2.2. The complete The complete ensiclopediaensiclopedia of Minerals by of Minerals by PetrPetr Korbel&MilanKorbel&Milan NovakNovak

3.3. The system of mineralogy, sixth edition The system of mineralogy, sixth edition by Dana, E.S., 1892by Dana, E.S., 1892