JEO253-Min-Pet

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JEO253-Min-Pet Assoc. Prof. Meral Dogan Dr.
Dogans homepage Lectures 3
Jeoloji Muhendisligi
Office 213
Office Hours
Office Phone [phone]
Email Address medogan_at_hacettepe.edu.tr
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Lab Syllibus Lab 1 Measurement of Physical
Properties of Minerals. Lab 2 Introduction to
the lattice, unit cell, and Miller indices.
Crystal systems, classes, and forms. Lab 3
Crystal systems and crystal classes
(continued). Lab 4, 5 and 6 Tectosilicates,
Phyllosilicates, Inosilicates, Cyclosilicates,
Sorosilicates, and Nesosilicates Lab 7
Carbonates, Halides, Phosphates, Sulfates
carbonates Lab 8 Native elements, oxydes and
hydroxytes Lab 9 Magmatic rocks Lab 10
Magmatic rocks Lab 11 Sedimentary rocks Lab
12 Metamorphic rocks
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Mineral idendification

• Renk-Color
• Parlaklik-Luster
• Transparency (or diaphaneity)
• Kristal sistemleri-Crystal Systems
• Olusum formlari-Technical Crystal Habits
• Descriptive Crystal Habits
• Ikizlenme-Twinning
• Dilinim-Cleavage
• Kirilma-Fracture
• Sertlik-Hardness
• Specific Gravity
• Cizgi rengi-Streak
• Birlikte bulundugu mineraller-Associated Minerals
  

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Color

• Usually, we notice the color of a mineral first.
  Some minerals are easily identified by color
  because they are never any other color. For
  example, malachite is always green.
• Keep in mind, however, that color by itself
  isn't enough to identify a mineral. Chemical
  impurities can change the color of a mineral
  without changing its basic make-up. For example,
  quartz in its purest form is colorless and clear
  as glass. Quartz with traces of iron becomes
  violet (amethyst). With traces of manganese, it
  turns pink (rose quartz). If quartz is exposed to
  radiation, it turns brown (smoky quartz).

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Kuvars-quartz (SiO2)
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Fluorit (CaF2)
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labrodorite

• color

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çizgi rengi-Some minerals leave a streak similar
to their natural color, such as cinnabar and
azurite

• Cinnabar Azurite

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American Museum of Natural History
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The terms used to describe luster (parlaklik)

• (Metalik) Metallic -- example gold )
• (Camsi)Vitreous (glassy) -- example quartz,
  tourmaline
• (Isiltili) Adamantine (brilliant) -- example
  diamond )
• (Reçine) Resinous (like resin or sap from a tree)
  -- example sphalerite )
• (Yagsi) Greasy or waxy -- example turquoise)
• (Incimsi) Pearly -- example talc)
• (Ipeksi) Silky -- example asbestos)
• (Topragimsi) Dull or earthy -- example bauxite)

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Metallic -high reflectivity like metal

• Galen (PbS)
• Sulfit

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Dull/earthy -shown by finely crystallized
minerals

• Hematit (Fe2O3)
• Oksit

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Mohs' Hardness Scale

• 1-Talc 
• 2-Gypsum
• 3-Calcite
• 4-Fluorite
• 5-Apatite
• 6-Orthoclase Steel  file
• 7-Quartz
• 8-Topaz 
• 9-Corundum 
• 10-Diamond

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Gypsum (CaSO4. 2H2O)

• Jips
• Sulfat

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Calcite-CaCO3

• Crystal
• (smooth
• faces)

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Elmas-Diamond

• Crystal
• Reflection

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Common Objects and Their Hardness Values

• 2.5 Fingernail
• 3.5 Penny
• 5.5 Glass
• 6.5 Steel knife
• An unknown sample can not be scratched by your
  fingernail (2.5) but it can be scratched by a
  penny (3.5), then it's hardness is between 2.5
  and 3.5. An example of a mineral that has a
  hardness between 2.5 and 3.5 is calcite (3).

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Specific Gravity

• is a special case of relative density defined as
  the ratio of the density of a given substance, to
  the density of water when both substances are at
  the same temperature.
• Substances with a specific gravity greater than 1
  are more dense than water, and those with a
  specific gravity of less than 1 are less dense
  than water.

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MineralsDensitySpecific gravity

• sulfur, graphite light 1-2
• gypsum, quartz medium 2-3
• fluorite, beryl medium -heavy 3-4
• corundum, most metal oxides heavy 4-6
• native gold, platinum heaviest 19

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Agir mineraller-Heaviest mineral

• Gold

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Kristal sekilleri-Crystal forms

• Cubic tetragonal hexagonal

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Tuz-Halite (salt) (NaCl)

• Cubic (intergrown)

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Pirit-Pyrite (FeS)

• cubic

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Isinsal-Radiating habit

• marcasite

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Klivaj-Dilinim (Cleavages (images web site))
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Fracture describes how a mineral breaks when
broken contrary to its natural cleavage planes.

• Chonchoidal fracture (quartz) is a smooth curved
  fracture with concentric ridges of the type shown
  by glass.
• fibrous or splintery (tremolite),
• Hackley (copper), is jagged fracture with sharp
  edges.
• Irregular

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Parting in Minerals

• Parting is a property that often gets confused
  with cleavage.
• There is good reason for that. Parting is a break
  along structural planes and is parallel to a
  possible face, just like cleavage. A good example
  is pyrite. However, parting differs from cleavage
  in some important ways.
• It can not be found in every specimen as is true
  of cleavage for most every cleavable mineral.
• It is not absolutely repeatable or reproducible
  as is cleavage down to theoretically the very
  atomic layers that cause cleavage.
• Parting is caused by pressures that are applied
  to a crystal or by twinning. The pressure breaks
  the crystal on a plane of weakness.

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Parting

• With pressure parting the actual break formed
  long before the crystal was excavated from the
  ground and may be due to tectonic or isostatic
  pressures that have been forced on the crystal.
• Most parting is seen as fracture lines that are
  incomplete or healed (the crystal continued to
  grow and sealed the break) and might appear as
  striations or planes of concentrated inclusions.