Earth Science | Sanuja Senanayake

Warning!

The descriptions of minerals may not be correct. I am in the process of completely deleting the texts. Thank you.

A better images of minerals can be found here

The following images are taken from a Samsung S III phone (Yes, you can’t believe the quality of detail on these images came from a 8 pix camera; contact me for technical/electronics detail on that) during the lab periods for Geology 311 (Mineralogy and Rocks) Winter 2013 at the University of Calgary.

Please click on the image on the left to access the larger original file.
Download the PDF Version here.

Igneous and Precipitate Minerals and Rocks

Sample	Properties
	Biotite Chem: K(Fe,Mg)₃AlSi₃O₁₀(OH)₂ Type: Sheet / Phyllosiclicate Structure: T-O-T+c structure Comp. Anio: (Si₄O₁₀)^4- Si-to-O: 2 ; 5 Cry. sys: Monoclinic Hd: 2.5 / 3.0 Hs: shiny black Col/pleo: tan/straw brown – dark brown or green – brown green Relief: moderate/+ve Cleve: perfect cleavage Twin: none Habit: massive/platy Ext: parallel / pebbly Int. col: 3rd – 4th Other: vitrous
	Calcite Chem: CaCO₃ Type: rhombohedral / trigonal Hd: 3 Hs: Colourless, white, grey colourless, maybe dirty Relief: high/positive Cleve: brittle / concoidal black with pastel stripes Twin: wiggly twins?!? Habit: crystalline/granular Ext: twinkling extinction Int. Col: VERY HIGH – 4th order Other: reacts readily with HCl
	Chromite (alt) Chem: FeCr₂O₄ Hs: brown streak, metallic luster, black granular Other: black under both xpl and ppl
	Garnet (Ca,Fe,Mg,Mn)3Al2Si3O12 Orthosilicate / Nesosilicate T-O structure Comp. An: SiO₄^4- Si-to-O: 1 ; 4 Type: isometric / cubic Hd: 6.5 – 7 Hs: red but variety too Col/pleo: clear/dirty – none Relief: high/positive Twin: none/uneven Habit: blocky/cubic Ext: NA
	Hornblende(type of amp) Chem: Ca₂(Mg,Fe,Al)₅(Al,Si)₈O₂₂(OH)₂ Type: Double Chain / Insolcate Structure: T-O-T structure Comp. Anio: (Si₄O₁₁)^6- Si-to-O: 4 ; 11 Cry. sys: Monoclinic Hd: 5.0 – 6.0 Hs: shiny black – underlaying green? Col/pleo: green-brown/light-darker Relief: high/positive Cleve: brittle – 2@60/120 Twin: simple twins (sometimes) Habit: bladed / fibrous Ext: inclined (14-25) Int. col: 2nd low – 3rd high? Other: dark opaque rim
	K-Feldspar (Orthoclase) Chem: KAlSi3O8 Type: Framework / Tectosilicate Comp. Anio: SiO₂ Si-to-O: 1;2 Cry: Monoclinic Hd: 6 Col/pleo: perthitic texture in pink-white Relief: very low/-ve Clev: 2@90 Twin: tarten/carlsbad Habit: tabular Int. col: 1st – grey/white
	Olivine Chem: (Fe,Mg)SiO₄ Type: Orthosilicate / Nesosilicate Comp. Anio: SiO₄^4- Si-to-O: 1 ; 4 Cry. sys: orthorhombic Hd: 6.5 – 7 Hs: yellow-green/olive green Col/pleo: colourless-olive green/none Relief: high/positive Cleve: none/irregular Habit: granular Ext. parallel to crystal faces Int. col: 2nd – 4th Other: rarely with quartz
	Orthopyroxene Chem:(Fe,Mg)2Si2O6 Type: Single Chain / Inosilcate TOT: T-O-T structure Comp. An: (SiO3)2- Si-O: 1 ; 3 orthorhombic Hd: 5.0 – 7 shiny black – dull weathered black pale green – pink Relief: moderate/+ve Cleve: 2@90 Habit: thin lamellar tabular parallel Int. Col.: 2nd – brown/yellow
	Plagioclase Chem: (Ca,Na)AlSi₃O₈ Type: Framework / Tectosilicate Comp. anio: SiO₂ Si-to-O: 1 ; 2 Cry. sys: Triclinic Hd: 6 – 6.5 Hs: grey – white Col/pleo: clear/dirty Relief: low/-ve Cleve: 2@90 Twin: albite/carlsbad/zone Habit: tabular Int. col: 1st – grey/white Other: zoning – Na rich rim / Ca rich core NOTE zoning in the last petrographic image.
	Quartz Chem: SiO₂ Type: Framework / Tectosilicate Comp. Anio: SiO₂ Si-to-O: 1 ; 2 Cry. sys: rhombohedral / trigonal Hd: 7 Hs: many colours Col/pleo: translucide clear/none Relief: low/negative Cleve: none/concoidal Twin: none Habit: massive/colmnar Ext. wavy Int. col: 1st – grey/white
	Tourmaline

Metamorphic/Sedimentary Minerals and Rocks

Sample	Properties
	Actinolite Chem: Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂ Inosilicate Monoclinic moderate/+ve green under PPL
	Andalusite Chem: Al₂SiO₅ Orthosilicate / Nesosilicate orthorhombic 7-7.5 red? Dark cross-like in x-section = chiasolite Col/pleo: clear/dirty – darker than Cordierite in ppl Relief: moderate/+ve Ext: parallel Int. Col: 1st – grey Other: looks like a dirtier Cordierite, higher relief LOW PRESSURE POLYMORPH
	Bedding vs Cleavage To be updated…
TBA	Blueschist This rock is formed deep underground about ~15 to 30 km of depth with between ~200 to 500 degrees Celsius. Blue colour is caused by Glaucophane mineral in the rock, which is a type of amphibole.
	Chert Chem: SiO₂ Hd: 7 Hs: black, grey, white Col/pleo: dirty brownish grains – none Relief: low/-ve Cleve: none/concoidal Habit: nodules Int. col: 1st – grey/white Notes: not a true mineral rather a siliceous ooze – fine crystalline in xpl. Hardness same as quartz
	Chalcedony and cavity filled with quartz Chalcedony is a type of fibrous cryptocrystalline to fine grained silica that forms in pores, cavities and vugs in pre-existing rocks by precipitation from Si-rich fluids that pass through the rocks. Agate is a more brightly coloured variety of chalcedony that typically shows colour banding, with the colours being due to trace amounts of iron and manganese (or, increasingly, to dyes!). The concentrically banded geodes that you see in rock shops are vugs that have been partially to wholly filled with chalcedony/agate.
	Chlorite Chem: (Mg,Fe)₃(Si,Al)₄O₁₀(OH)2*(Mg,Fe)₃(OH)₆ Sheet / Phyllosillicate T-O-T structure Monoclinic Hd: 2-2.5 Hs: green clear – green Relief: high/positive Cleve: perfect cleavage foliated masses – 2nd – Berlin Blue Other: has inclusions
	Coal To be updated…
	Dolomite CaMg(CO3)₂ rhombohedral / trigonal Hd: 3.5 – 4 Hs: Colourless, white, grey (due to impurities, it can be many colours) Col/pleo: colourless/none Relief: low-moderate Cleve: perfect Twin: black with pastel stripes, wiggly twins?!? Habit: crystalline/granular Ext: twinkling extinction Int. Col: VERY HIGH – 4th order Other: Sugary texture may only be observed in finely crystalline dolomite as opposed to curved crystals faces of coarse dolomite. HCL reaction is very poor to none. It is extremely difficult to separate dolomite from calcite using a thin section. Precipitate mineral!
	Epidote Chem: FeAl₂O-OH[Si₂O₇][SiO₄] Sorosilicate Monoclinic 6 silver/pistachio green yellow or green colourless to greenish yellow Relif: high/+ve brittle – planar lamellar (not common) fibrous, coarse to fine granular, massive. 3rd – bright green vitrous, Notes: pearly (Regional and contact metamorphic rocks)
	Garnet with pressure shadows Please check the information for the mineral in the igneous table above.
	Hematite (Ore) (B), Quartz (A) On the XPL photo, you can see the radiating cement of quartz (A) and the think black-brown (to dark reddish) outline of hematite (B) Hs: red-brown streak, steel gray and metallic shiny
	Kyanite Chem: Al₂SiO₅ Type: Triclinic Hd: 5.5-7 Hs: blue Col/pleo: clear Relief: high/+ve Twin: simple twins (sometimes) Habit: bladed / tabular Ext: inclined Int. Col: 1st – grey/yellow Other: HIGH PRESSURE POLYMORPH, may show stepped appearance like “tree-bark” in thinsection
	Mudstone with mud interclasts AND with interclasts of fragments
	Muscovite Chem: KAl3Si3O10(OH)2 Sheet / Phyllosilicate T-O-T+c structure Comp. An: (Si4O10)4- 2 ; 5 Monoclinic Hd: 2.5 / 4.0 Hs: silvery/white – colourless Col/pleo: clear/none Relief: moderate/+ve Cleave: perfect cleavage Twin: none Habit:massive/platy parallel / pebbly 2nd – 3rd vitrous
	Ooids The second image (XPL) shows with stylolites…
	Fossils in Packstone to be updated…
	Serpentine to be updated…
	Sillimanite First two images are from an altered formation of the mineral in igneous rocks. Chem: Al2SiO5 orthorhombic Hd: 7.5 Hs: white/yellow Col/pleo: clear/none Relief: moderate to high/+ve Habit: cylindrical/fibrous Int. col: 2nd – pink
	Staurolite Chem: (Fe,Mg,Zn)₂Al₉(Si,Al)₄O₂0(OH)₄ Type: Orthosilicate / Nesosilicate Monoclinic Hd: 7-7.5 Hs: dark brown / black Col/pleo: honey/potato yellow – none (ppl) Relief: high/+ve Cleve: subconcoidal Ext: zoning? Habit: intersecting prisms like a cross Int. Col: 2nd – mid/high yellow Other: poikiloblastic (air bubbles), “stauros” greek for cross – 2intersecting prisms HEXAGONAL SHAPED EUHEDRAL
	Tremolite Monoclinic 5.0-6.0 white, brown… colourless – none moderate/+ve brittle 2@60/120 silky, fibrous 2nd – bright turquoise similar to sillimanite in handsample
	Zebra Dolostone This type of rocks were originally limestone, now transformed into ‘Zebra’ dolomite. At least partially fracture controlled, because of planar zones of coarse, light-coloured dolomite in darker, fine grained host. However, all of the rock now consists of dolomite, including the dark fine grained portions, suggesting an earlier period of pervasive dolomitization.
	Halite and Gypsum Halite is a Precipitate! Since it is white in colour, hand samples may be contaminated with other minerals causing it to appear in different coulours. The Halite is pretty much table salt, but do not taste it. Gypsum has a sugary texture, curved crystal surfaces

To be updated…
Glass

List of Minerals Properties To Be Updated

Please read what PPL and XPL.

Clinopyroxene Ca(Fe,Mg)Si2O6 Single Chain / Inosilcate T-O-T structure (SiO3)2- 1 ; 3 Monoclinic 5.0 – 7 shiny black – dull weathered black earthy/brown – nonpleochroic moderate/+ve 2@90 sometimes carlsbad / zoning thin lamellar tabular inclined (35-48) 2nd – low/mid

Apatite Ca5(PO4)3(F,Cl,OH) – – – – Hexagonal 5 very small usually – never see clear/none high/positive none/concoidal none six sided euhedral – 1st – grey/white usually a captured/ looks standing up… looks like quartz but really small

Tourmaline Na(Fe,Mg)3Al6(BO3)3(Si6O18)(OH)4 Ring / Cyclosilicate – Si6O1812- 1 ; 3 rhombohedral / trigonal 7 black hexagonal prisms seen in class? variable – variable moderate/+ve none none striated prism parallel 1st – 2nd – moderate

Cordierite Al2SiO5 Ring / Cyclosilicate orthorhombic 7-7.5 clear/dirty – lighter than Andalusite, has border moderate/+ve subconcoidal sector twinning 1st – grey/white looks like a cleaner andalusite, has patchy domains that extinct at different angles within crystal, has sometimes brown outlined border around crystal

Glaucophane Double Chain / Insolcate Monoclinic 5.0 – 6.0 grey/lavender blue lavender blue to striking blue (ppl) bladed / fibrous 3rd – bright blue

titanite pale brown – none v. high/ +ve

phlogopite

lawsonite mod. High relief

—OLD DATA–

Staurolite: pleochroic (light -dark yellow), cruciform,+

Andalusite: 2 @ 90, inclusion of other minerals, high relief, cloudy in PPL.

Cordierite: blobby/blocky, low interference, other minerals inclusion. And/cord look like quartz.

Silimanite: hand elongated, white bladed, thin pleochroic (yellow-orange), second order, high relief.

Chlorite: green under PPL. Purple/brown under XPL.

Clinopyroxene: higher birefringence and non-parallel extinction.

Epidote: “stain glass” yellow-green-blue under XPL. hand s vitreous.

Glaucophane: blue amphibole found in blueschists.

Tremolite: white in PPL, found in calcitic rocks only.

Warning!

Scale images are Copyrighted to The Geological Society of America. Please check their website at, http://geosociety.org. If you would like to add more “Facts” to this page, please contact me.

The following information is published for fun and NOT for any scientific value. Please do not take any information on this page as a fact or a hypothesis. This page is created base on some funny ideas going around in Geology.

	Quaternary glaciation (last ice age): resulted in Sid, Diego and their friends Zeke, Carl and others became friends with a human child. Rise of human civilization; gave birth to modern day self-centered idiots who destroy the Earth. For the first time aliens from the planet LV-426 probe a human female for biological experiments. Biological break though in human evolution was found when a man with one nut, known as A. Hitler, was discovered when his party came to power in Germany. Strong evidence suggesting our great grand parents were monkeys who butt-%#^$k came to life. The epidemic HIV/AIDS has been attributed to modern human-monkey interactions in the wild.
	Due to lack of water to reduce friction during sex, dinosaurs went extinct (Cretaceous). Break up of Pangaea(Jurassic) into Gondwana and Laurasia since they can’t resolve their three-way relationship problems anymore.
	For the first time, large trees and shrubs were grown. Opium and marijuana(Cannabis) became very popular among the micro-organisms causing “ya-man” disease. Carbonated drinks during this period have lead to major teeth problems among mammal population. The acid in their coke have dissolved their teeth during Carboniferous period. Landmasses fall in love creating the new marriage, Pangaea. It won’t last very long since each other have accused of cheating from the very beginning.
	Moon was formed as result of aliens attacking the Earth with nukes. One of the nuke bombs hit the Earth so hard, creating the basin near Mexico. Earth was sexy hot during this time; too bad with age, she became what she is today.

Sanuja Senanayake

Category Archives: Earth Science

Minerals and rocks from GLGY311 Lab

A better images of minerals can be found here

Please click on the image on the left to access the larger original file.
Download the PDF Version here.

Igneous and Precipitate Minerals and Rocks

Metamorphic/Sedimentary Minerals and Rocks

List of Minerals Properties To Be Updated

Updated Geologic Time Scale

Basic construction of a Mohr Circle

Stereographic projection for structural analysis

Controversial Geological history of Earth

Standing on the shoulders of giants

A better images of minerals can be found here

Please click on the image on the left to access the larger original file.Download the PDF Version here.

Igneous and Precipitate Minerals and Rocks

Metamorphic/Sedimentary Minerals and Rocks

List of Minerals Properties To Be Updated

Standing on the shoulders of giants

Please click on the image on the left to access the larger original file.
Download the PDF Version here.