Microcline is an important igneous rock-forming potassium feldspar mineral. Biotite is an iron-rich sheet silicate mineral that forms weakly bound sheets. Calcite is the most stable polymorph of calcium carbonate and commonly forms trigonal-rhombohedral crystals. Fluorite is a colorful mineral composed of calcium fluoride that is used for ornamental purposes and in industrial applications such as smelting fluxes.

1. 1. Microcline(K-Feldspar)
• Microcline(K-Feldspar)

2. • Microcline (KAlSi3O8) is an important igneous
rock-forming tectosilicate mineral. It is a
potassium-rich alkali feldspar.

3. 2. Milky quartz sample

4. 2. Milky quartz sample
Crystal habit 6-sided prism ending in 6-sided
pyramid (typical), drusy, fine-
grained to
microcrystalline, massive
Crystal system α-quartz: trigonal trapezohedral class 3
2; β-quartz: hexagonal62

5. 3. Biotite

6. 3. Biotite
• . Biotite was named by J.F.L. Hausmann in
1847 in honour of the French physicist Jean-
Baptiste Biot, who, in 1816, researched the
optical properties of mica, discovering many
unique properties

7. 3. Biotite
• Biotite is a sheet silicate. Iron, magnesium,
aluminium, silicon, oxygen, and hydrogen
form sheets that are weakly bound together
by potassium ions. It is sometimes called "iron
mica" because it is more iron-rich than
phlogopite. It is also sometimes called "black
mica" as opposed to "white mica" (muscovite

9. 4. muscovite

10. 5. Albite (plagioclase feldspar)

11. 5. Albite (plagioclase feldspar)

12. 6. Hornblende (amphibole)

13. 6. Hornblende (amphibole)
• containing ions of iron and/ormagnesium in
their structures. Amphiboles can be
green, black, colorless, white, yellow, blue, or
brownAmphiboles crystallize into two crystal
systems, monoclinic and orthorhombic. In
chemical composition and general
characteristics they are similar to
the pyroxenes

14. 6. Hornblende (amphibole)
• Most apparent, in hand specimens, is that
amphiboles form oblique cleavage planes (at
around 120 degrees), whereas pyroxenes have
cleavage angles of approximately 90 degrees.
Amphiboles are also specifically less dense
than the corresponding pyroxenes.

15. 7. Augite (pyroxene)

16. 7. Augite (pyroxene)
• Augite is a common rock forming single chain
inosilicate mineral with formula
(Ca,Na)(Mg,Fe,Al,Ti)(Si,Al)2O6.
The crystals are monoclinic and prismatic.
Augite has two prominent cleavages, meeting
at angles near 90 degree

17. 8. Olivine
• Olivine occurs in both mafic and ultramafic igneous
rocks and as a primary mineral in
certain metamorphic rocks. Mg-rich olivine
crystallizes from magma that is rich in magnesium
and low in silica.
• That magma crystallizes to mafic rocks such
asgabbro and basalt

18. 8. Olivine

19. 9. Kaolinite

20. 9. Kaolinite

21. 9. Kaolinite
• group of industrial minerals, with the chemical
composition Al2Si2O5(OH)4. It is a layered silicate mineral, with
one tetrahedral sheet linked through oxygen atoms to
one octahedral sheet of alumina octahedra.Rocks that are
rich in kaolinite are known as kaolin or china clay.
• The name is derived from Chinese Kao-Ling

22. 10. Calcite

23. 10. Calcite
• Calcite is a carbonate mineral and the most
stable polymorph of calcium
carbonate(CaCO3). The other polymorphs are
the minerals aragonite and vaterite. Aragonite
will change to calcite at 380–470°C,[5] and
vaterite is even less stable

24. 10. Calcite crystals
• Calcite crystals are trigonal-
rhombohedral, though actual
calcite rhombohedra are rare as natural
crystals.
• . It may occur as fibrous, granular, lamellar, or
compact. Cleavage is usually in three
directions parallel to the rhombohedron form.
Its fracture is conchoidal, but difficult to
obtain.

25. 10. Calcite crystals
• It has a defining Mohs hardness of 3, a specific
gravity of 2.71, and its luster is vitreous in
crystallized varieties. Color is white or
none, though shades of
gray, red, orange, yellow, green, blue, violet, brow
n, or even black can occur when the mineral is
charged with impurities.
• Calcite is transparent to opaque and may
occasionally
show phosphorescence orfluorescence

26. 11. Dolomite

27. 11. Dolomite
• Dolomite is a carbonate mineral composed
of calcium magnesiumcarbonate CaMg(CO3)2.
• Dolomite is also used to describe
the sedimentary carbonate rock dolostone which
is composed predominantly of the mineral
dolomite. Limestone which contains smaller
amounts of the mineral dolomite is referred to
as dolomitic limestone, or in the older
literature magnesian limeston

28. 12. Bauxite
• Bauxite is an aluminium ore and is the main source of
aluminium. This form of rock consists mostly of
the minerals gibbsite Al(OH)3, boehmite γ-
AlO(OH), and diaspore α-AlO(OH), in a mixture with
the two iron oxides goethite and haematite, the clay
mineralkaolinite, and small amounts of anatase TiO2.
Bauxite was named after the village Les Baux in
southern France, where it was first recognised as
containing aluminium and named by the French
geologist Pierre Berthier in 1821

29. 13. Talc
• (derived from Persian: tālk; Arabic: talk)
is a mineral composed of hydrated
• magnesium silicate with the chemical formula
H2Mg3(SiO3)4 or Mg3Si4O10(OH)2. In loose form, it
is the widely used substance known as talcum
powder. It has a perfect basal cleavage, and the
folia are non-elastic, although slightly flexible. It is
the softest known mineral and listed as 1 on
the Mohs hardness scale

30. 13. Talc
• It can be easily scratched by a fingernail. It is
also sectile (can be cut with a knife). It has
a specific gravity of 2.5–2.8, a clear or
dusty luster, and is translucent to opaque. Talc
is not soluble in water, but it is slightly soluble
in dilute mineral acids. Its colour ranges
from white to grey or green and it has a
distinctly greasy feel. Its streak is white

31. 13. Talc
• Talc is a metamorphic mineral resulting from
the metamorphism of magnesian minerals
such as serpentine, pyroxene, amphibole,
• olivine

32. 14. Garnets
• Garnets possess similar physical properties
and crystal forms but different chemical
compositions. The different species
are pyrope, almandine, spessartine, grossular(
varieties of which are hessonite or cinnamon-
stone and tsavorite), uvarovite andandradite.
The garnets make up two solid solution series:
pyrope-almandine-spessarite and uvarovite-
grossular-andradite

33. 14. Garnets

34. Magnetics used in garnet series
identification
• For gem identification purposes, a pick-up
response to a strong neodymium magnet
separates garnet from all other natural
transparent gemstones commonly used in the
jewelry trade.

35. Magnetics used in garnet series
identification
• Magnetic susceptibility measurements in
conjunction with refractive index can be used
to distinguish garnet species and varieties, and
determine the composition of garnets in
terms of percentages of end-member species
within an individual gems

36. 16. Halite

37. 16. Halite

38. 16. Halite

39. 16. Halite

40. 17. Gypsum
• of calcium sulfate dihydrate, with thechemical
formula CaSO4·2H2O.[3] It can be used as
a fertilizer, is the main constituent in many forms
of plaster and is widely mined. A very fine-
grained white or lightly tinted variety of gypsum,
called alabaster, has been used for sculpture by
many cultures including Ancient
Egypt, Mesopotamia and the Nottingham
alabasters of medieval England. It is the definition
of a hardness of 2

41. 18. Chalcopyrite
• a copper iron sulfide mineral that crystallizes
in the tetragonal system. It has the chemical
composition CuFeS2. It has a brassy to golden
yellow color and a hardness of 3.5 to 4 on
the Mohs scale. Its streak is diagnostic as
green tinged black.
• On exposure to air, chalcopyrite oxidises to a
variety of oxides, hydroxides and sulfates

42. 18. Chalcopyrite

43. The unit cell of chalcopyrite. Copper is
shown in pink, iron in blue and sulfur
in yellow.

44. zinc blende ZnS (sphalerite
• Crystallographically the structure of
chalcopyrite is closely related to that of zinc
blende ZnS (sphalerite). The unit cell is twice
as large, reflecting an alternation of Cu+ and
Fe3+ ions replacing Zn2+ ions in adjacent cells.
In contrast to the pyritestructure chalcopyrite
has single S2- sulfide anions rather than
disulfide pairs. Another difference is that the
iron cation is not diamagnetic low spin Fe(II)
as in pyrite

45. 19. Galena

46. Lead Sulfide –Pd(II)S
• Galena is one of the most abundant and
widely distributed sulfide minerals. It
crystallizes in the cubic crystal system often
showing octahedral forms. It is often
associated with the
minerals sphalerite, calcite and fluorite

47. Simple Cubic crystal system
Lead Sulfide –Pd(II)S

48. 20. Limonite
• Limonite is an iron ore consisting of a mixture
of hydrated iron(III) oxide-hydroxides in
varying composition. The generic formula is
frequently written as FeO(OH)·nH2O, although
this is not entirely accurate as the ratio of
oxide to hydroxide can vary quite widely.
Limonite is one of the two principle iron
ores, the other being hematite, and has
been mined for the production of iron since at
least 2500 BCE

49. 20. Limonite
Limonite: hydrated iron(III) oxide-hydroxides

50. Fluorite
• (also called fluorspar) is a halide
mineral composed of calcium fluoride, CaF2. It
is an isometric mineral with a cubic habit,
though octahedral and more complex
isometric forms are not uncommon.
• Fluorite is a colorful mineral, both in visible
and ultraviolet light, and the stone has
ornamental and lapidary uses.

51. Fluorite
• Industrially, fluorite is used as a flux for smelting, and
in the production of certain glasses and enamels. The
purest grades of fluorite are a source of fluoride
for hydrofluoric acid manufacture, which is the
intermediate source of most fluorine-containing fine
chemicals. Optically clear transparent fluorite lenses
have low dispersion, so lenses made from it exhibit
less chromatic aberration, making them valuable in
microscopes and telescopes. Fluorite optics are also
usable in the far-ultraviolet range where conventional
glasses are too absorbent for us

52. Fluorite
• Optically clear transparent fluorite lenses have
low dispersion, so lenses made from it exhibit
less chromatic aberration, making them
valuable in microscopes and telescopes.
Fluorite optics are also usable in the far-
ultraviolet range where conventional glasses
are too absorbent for us

53. Fluorite

54. Fluorite

55. fluorescence of fluorite
• Many samples of fluorite
exhibit fluorescence under ultraviolet light, a
property that takes its name from fluorite.[ Many
minerals, as well as other substances, fluoresce.
• Fluorescence involves the elevation of electron
energy levels by quanta of ultraviolet
light, followed by the progressive falling back of
the electrons into their previous energy
state, releasing quanta of visible light in the
process

56. fluorescence of fluorite
• In fluorite, the visible light emitted is most
commonly blue, but red, purple, yellow, green
and white also occur. The fluorescence of
fluorite may be due to mineral impurities such
as yttrium, ytterbium, or organic matter in the
crystal lattice

57. Graphite
• allotrope of carbon. It was named by Abraham
Gottlob Werner in 1789 from the Ancient
Greek γράφω (graphō), "to draw/write", for
its use in pencils, where it is commonly
called lead (not to be confused with the
metallic element lead).
Unlike diamond (another carbon
allotrope), graphite is an electrical
conductor, a semimetal. It
is, consequently, useful in such applications
as arc lampelectrodes.

58. Graphite
• . Therefore, it is used in thermochemistry as
the standard state for defining the heat of
formation of carbon compounds. Graphite
may be considered the highest grade
ofcoal, just above anthracite and alternatively
called meta-anthracite, although it is not
normally used as fuel because it is difficult to
ignite.

59. Graphite

60. Graphite

62. •
• Graphite
• Hematite
• Magnetite (lodestrone)
• Sphalerite

64. Begin lab 4 and lab 5 with faith heart
and skill