MINERALOGY 1

MINERALOGY IS THE BRANCH OF THE EARTH SCIENCE THAT IS CONCERNED WITH THE STUDY OF MINERALS AND THEIR PHYSICAL AND CHEMICAL PROPERTIES WITHIN MINERALOGY. THERE ARE ALSO THOSE WHO STUDY HOW MINERALS ARE FORMED WHERE THEY ARE GEOGRAPHICALLY LOCATED AS WELL AS THEIR POTENTIAL USES.

MINERALOGY IS THE SIMPLEST WAY TO STUDY AND CLASSIFY MINERALS IS TO DO SO BASE ON THEIR PHYSICAL ATTRIBUTES. THESE CAN INCLUDE THE MICROSCOPIC STRUCTURE OF THE MINERAL CRYSTALS THE WAY IN  WHICH THE MINERALS CLEAVES WHEN STRUCK AND ITS HARDNESS DESCRIBES THIS PARTICULAR PROPERTY.

MINERAL IS A NATURALLY OCCURRING HOMOGENOUS SOLID WITH A DEFINITE CHEMICAL COMPOSITION AND AN ORDERED ATOMIC ARRANGEMENT. IT IS USUALLY FORMED BY INORGANIC PROCESSES. IT IS A BUILDING BLOCK OF ROCKS.

FIVE CRITERIA OF A MINERAL

1. THE SUBSTANCE MUST EXIST AS A " SOLID" UNDER NORMAL CONDITIONS ON EARTH.

2. THE SUBSTANCE MUST BE "NATURALLY OCCURRING" ON EARTH, NOT MAN-MADE.

3. THE SUBSTANCE MUST BE "INORGANIC" NOT LIVING OR MADE FROM LIVING THINGS

4. THE SUBSTANCE MUST HAVE A "FIXED CHEMICAL FORMULA" MADE OF SPECIFIC ELEMENTS

5. THE ATOMS THAT MAKE-UP THE SUBSTANCE MUST BE ARRANGED IN AN ORDERLY STRUCTURE.

IMPORTANCE OF MINERALOGY

SINCE BEFORE HISTORIC TIME, MINERALS HAVE PLAYED A MAJOR ROLE IN HUMANITY'S WAY OF LIFE AND STANDARD OF LIVING. WITH EACH SUCCESSIVE CENTURY THEY HAVE BECOME INCREASINGLY IMPORTANT AND TODAY WE DEPEND ON THEM IN COUNTLESS WAYS. CONSTRUCTION OF SKY SCRAPPERS, TO THE MANUFACTURE OF COMPUTERS, CELLPHONE, TELEVISION, ETC. MODERN CIVILIZATION DEPENDS ON THE PRODIGIOUS USE OF MINERALS.

A FEW MINERALS SUCH AS TALC, ASBESTOS, AND SULFUR ARE USED ESSENTIALLY AS THEY COME FROM THE GROUND, BUT MOST ARE FIRST PROCESSED TO OBTAIN A USEABLE MATERIAL, SOME OF THE MORE FAMILIAR OF THESE PRODUCTS ARE BRICKS, GLASS, CEMENT PLASTER, AND A SCORE OF METALS RANGING FROM IRON TO GOLD.

METALLIC ORES AND INDUSTRIAL MINERALS ARE MINED ON EVERY CONTINENT WHEREVER SPECIFIC MINERALS ARE SUFFICIENTLY CONCENTRATED TO BE ECONOMICALLY EXPECTED.

NAMING OF MINERALS

THE CAREFUL DESCRIPTION AND IDENTIFICATION OF MINERALS OFTEN REQUIRE HIGHLY SPECIALIZED TECHNIQUES SUCH AS CHEMICAL ANALYSIS AND MEASUREMENT OF PHYSICAL PROPERTIES, AMONG WHICH ARE THE SPECIFIC GRAVITY, OPTICAL PROPERTIES AND X-RAY PARAMETERS WHICH RELATE TO THE ATOMIC STRUCTURE OF MINERALOGY.

MINERALS MAY BE GIVEN NAMES OF THE BASIS OF SOME PHYSICAL PROPERTIES AND X-RAY PARAMETERS WHICH RELATE TO THE ATOMIC STRUCTURE OF MINERALS.

MINERALS MAY BE GIVEN NAMES ON THE BASIS OF SOME PHYSICAL PROPERTY OR CHEMICAL ASPECT OR THEY MAY BE NAMED AFTER A LOCALITY A PUBLIC FIGURE, A MINERALOGIST, OR ALMOST ANY OTHER SUBJECT CONSIDERED APPROPRIATE SOME EXAMPLES OF MINERAL NAMES AND THEIR DERIVATIONS AS FOLLOWS:

1. albite (NaAlSi₃O₈) L albus white
2. rhodonite (MnSiO₃) rose quatz Gk rhodon rose pink color
3. chromite (FeCr₂O₄) chromium
4. magnetite (Fe₃O₄) magnetic properties
5. franklinite (ZnFe₂O₄) Franklin Furnace, New Jersey
6. sillimanite (Al₂SiO₅) Bengjamine Silliman

1. HARDNESS IS THE RESISTANCE THAT THE SURFACE OF A MINERAL OFFERS TO SCRATCHING RELATIVE HARDNESS CAN BE DETERMINED BY MEANS OF COMPARISON WITH THE MINERALS BELONGING TO THE MOH'S SCALE OF HARDNESS

THE HARDNESS OF A MINERAL MIGHT THEN BE SAID TO BE ITS SCRATCHABILITY

01 TALC (SOFTEST)
02 GYPSUM
03 CALCITE
04 FLOURITE
05 APATITE
06 ORTHOCLASE/ FELDSPAR
07 QUATZ
08 TOPAZ
09 CORUNDUM
10 DIAMOND (HARDEST)

THE DEGREE OF HARDNESS IS DETERMINED BY OBSERVING THE COMPARATIVE EASE OR DIFFICULTY WITH WHICH ONE MINERAL SCRATCHED BY ANOTHER OR BY A FILE OR KNIFE.

2. MAGNETISM IS THE PROPERTY OF A MINERAL TO BE ATTRACTED TO A HAND MAGNET. MINERALS MAYBE CLASSIFIED INTO THREE CATEGORIES ACCORDING TO MAGNETIC PROPERTIES

FERROMAGNETIC (STRONGLY ATTRACTED)
PARAMAGNETIC (SLIGHTLY ATTRACTED)
DIAMAGNETIC (NOT ATTRACTED)

3. STREAK IS THE COLOR OF THE POWDER OF THE MINERAL. IT IS USUALLY THOUGH NOT ALWAYS OBTAINED BY RUBBING IT ON UNGLAZED PORCELAIN OR BY SCRAPPING IT WITH A HARD OBJECT.

4. EFFERVESCENCE IS THE FIZZLING SOUND HEARD COMBINED WITH BUBBLING SEEN WHEN A CARBONATE MINERAL REACTS WITH AN ACID THUS, IT IS A DIAGNOSTIC TEST FOR THE CARBONATE GROUP OF MINERALS.

5. TENACITY IS THE RESISTANCE THAT A MINERAL OFFERS TO BREAKING, CRUSHING, BENDING, OR TEARING IN SHORT, ITS COHESIVENESS IS KNOWN AS TENACITY

A. BRITTLE - EASILY BREAKS OR POWDERS
B. MALLEABLE - CAN BE HAMMERED OUT INTO THIN SHEET
C. SECTILE - CAN BE CUT INTO THIN SHAVINGS WITH A KNIFE
D. DUCTILE - CAN BE DRAWN INTO A WIRE
E. FLEXIBLE - BENDS BUT DOES NOT RESUME ITS ORIGINAL SHARE WHEN THE PRESSURE IS RELEASED
F. ELASTIC - AFTER BEING BENT, WILL RESUME ITS ORIGINAL POSITION UPON THE PRESSURE

6. COLOR IS THE EFFECT PRODUCED BY THE COMBINATION OF WAVELENGTHS OF LIGHT INCIDENT ON THE SURFACE OF THE MINERAL, WHICH CAN REACH THE OBSERVER'S EYES

7. DIAPHANEITY IS THE RELATIVE OF MINERALS TO ALLOW LIGHT TO PASS THROUGH

TRANSPARENT - WHEN ALL OBJECTS MAY BE DISTINCTLY RECOGNIZED THROUGH A LARGE OR SMALL  PIECE OF IT

TRANSLUCENT - WHEN ALL OBJECTS MAY BE DISTINCTLY RECOGNIZED THROUGH IN-OUT LIGHT IS TRANSMITTED ONLY THROUGH THE EDGES OF A LARGE  OR SMALL PIECE ; IF THE MINERAL SHINES TROUGH THE EXTREMITIES OR EDGES WHEN HELD AGAINST THE LIGHT IT IS SAID TO BE TRANSLUCENT AT THE EDGES

OPAQUE - WHEN NO PERCEPTIVE DEGREE OF LIGHT IS TRANSMITTED EVEN THROUGH THE THINNER PIECE

8. PARTING IS WHEN THE MINERALS BREAK ALONG PLANES OF STRUCTURAL WEAKNESS; THEY HAVE PARTING THE WEAKNESS MAY RESULT FROM PRESSURE OR TWINNING AND BECAUSE IT IS PARALLEL TO RATIONAL CRYSTALLO-GRAPHIC  PLANES, IT RESEMBLES CLEAVAGE

HOWEVER PARTING UNLIKE CLEAVAGE IS NOT SHOWN BY ALL SPECIMENS BUT ONLY THOSE THAT ARE TWINNED OR HAVE BEEN SUBJECTED TO THE PROPER PRESSURE

9. FRACTURE IS THE APPEARANCE OF THE SURFACE OF A MINERAL WHEN IT DOES NOT BREAK ALONG CLEAVAGE PLANE. FRACTURE CAN BE DESCRIBED BY THE FOLLOWING TERMS

A. SCALY - THE SURFACE IS NOT INTERRUPTED BY MANY NOTICEABLE PROTUBERANCES BUT WITH FEW SMALL SCALES

B. CONCHOIDAL - THE SURFACE CONSISTS OF FLAT ROUNDED PROTUBERANCES ACCOMPANIED BY CIRCULAR GROOVES AS IN CLAM SHELLS

C. UNEVEN - THE SURFACE IS ENTIRELY INTERRUPTED BY ANGULAR LARGE AND SMALL PROTUBERANCES

D. HACKLY - THE SURFACE IS JAGGED AND WITH SHARP EDGES

E. FIBROUS - CERTAIN LARGER PARTS RESEMBLE FIBERS CAN BE DISTINGUISHED ON THE SURFACES AS IN WOOD

F. FOLIATED - SURFACE IS MADE UP OF PARTS RESEMBLING PLANES WITH LENGTH AND BREADTH NEARLY  EQUAL