THE GEORGIA
MINERAL HERITAGE 
PROJECT 
"Minerals of the Wolf Creek Formation"
Gwinnett County
Norcross Quadrangle

 
[GMHP Protocol Page #1] 
RESEARCH AND COLLECTING PROTOCOL

General Information

       Project Number: GWINNETT-01
Project Participants: DAVID BABULSKI

           Date Started: 6/1999 - 4/2000

      Contact Person: DAVID BABULSKI

                     E-Mail: DBABULSK@LANIER.COM   Telephone Number:  770-985-1772

Mineral species reported at this site: 
 HORNBLENDE, EPIDOTE, PIEMONTITE, CHABAZITE, PYRITE, CHALCOPYRITE, CLINOZOISITE,
 DRAVITE var. Tourmaline, PREHNITE, CHLORITE, CARNET var. Almandine, KAOLINITE,
 CALCITE, SULPHUR, HYALITE OPAL



[GMHP Protocol Page #1A] 
Site Geographical Data for project: #GWINNETT-01 Date: 4/2000
County: GWINNETT
Nearest City, Town or Village: DULUTH
Nearest major access road: SATELLITE BLVD., OLD NORCROSS RD.

Is site on public  [       ]  or private  [  X  ] property?
If private property, owner's name, address and telephone number:

                 MORGAN CORP.  770-239-7487
CRESCENT RESOURCES 770-622-9888

Is the site ecologically sensitive?   YES   [       ] ,  NO  [  X  ]
Is the site being adversely impacted by development?   YES [  X  ]  NO [      ]
Is collecting permitted?  YES  [      ] ,  NO [  X  ] Site is extinct!
Collecting level? Unlimited [ NA ], Fee based collecting [      ], By permission [      ] 
If permission required, contact person:    NA _________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________

Is site location publishable?  YES  [  X  ]  NO  [       ]
If YES, Latitude and Longitude of site: Lat.: 33 55', Long.: 84 10'



[GMHP Protocol Page #2] 

Site Geographical Data for project: #GWINNETT-01 Date: 4/2000

Georgia Geological Province in which the mineral occurrence is located:
Ridge and Valley [     ],  Blue Ridge [     ],  Piedmont [ X ],  Coastal Plain[     ] 

Mineral occurrence is in which Geological Survey Quadrangle: NORCROSS (7 1/2 Quadrangle)

Mineral occurrence is in what geological formation? 

 WOLF CREEK FORMATION

If mineral occurrence is as float, what geological formation is it most likely associated with? 

 NA 

What is the host rock type in which the mineral(s) found? 

 AMPHIBOLITE

If applicable, what is strike and dip of host rocks at mineral occurrence?

     COMPLEX FOLDING OF HOST ROCKS.  THE AXIS OF THE FOLDS TREND IN A N 80 E DIRECTION.   MINERAL OCCURRENCE DOES NOT SEEM RELATED TO LOCATION WITHIN THE FOLDING  COMPLEX.

If applicable, briefly describe other structural characteristics of the host rocks

    THINLY LAMINATED FINE GRAINED AMPHIBOLITE WITH EYE PODS OF EPIDOTE, CLINOZOISITE,  QUARTZ.  IN SOME CASES, THESE PODS SHOWING EN E CHELON FRACTURES.  THE MOST HEAVILY MINERALIZED AREA LOCATED IN COARSE GRAINED AMPHIBOLITE.

Does the mineral occurrence appear to be of primary or secondary origin?

     THE FOLLOWING APPEAR TO BE PRIMARY: HORNBLENDE, EPIDOTE, PIEMONTITE, PYRITE, DRAVITE TOURMALINE, CLINOZOISITE.  SECONDARY MINERALS:  CALCITE, CHALCOPYRITE, CHABAZITE, PREHNITE, CHLORITE, SULPHUR, KAOLINITE.  Note:  The GARNET appears to be primary associated with QUARTZ.



[GMHP Protocol Page #3] 
Sketch of Geological Setting for project # GWINNETT-01 Date: 4/2000

[Link to Sketch of Geological Setting]



[GMHP Protocol Page #4, A, B] 
Site Mineralogical Data for project # GWINNETT-01 Date: 4/2000

[Link to mineralogical data and sketch showing location of mineral occurrence(s) at this site]



[GMHP Protocol Page #5] 
Site Mineralogical Data – Page 2 for project # GWINNETT-01 Date: 4/2000

Description of mineral species 1: HORNBLENDE
     Black to blue gray laminar crystals, most cases crystals very small.  In a few vugs there are crystals to 3-4mm in length.

Test used in identification of the mineral species: 
     Association, optical properties.

Description of mineral species 2: CLINOZOISITE
     Light gray green blocky crystals and masses in eye pods.  Some examples of tightly interlocking crystal sprays.  Associated with Epidote.

Test used in identification of the mineral species: 
     Hardness, color, optical properties.

Description of mineral species 3: EPIDOTE
     Typically in granular form within "eye pods" in amphibolite.  Some very nice gemmy green crystals in vugs - primarily in the coarse grained amphibolite at site "A".

Test used in identification of the mineral species: 
     Crystal form, hardness, color, optical properties, blowpipe tests

Description of mineral species 4: PIEMONTITE
     Occurs with epidote in "eye pods" exhibiting en echelon fracture.  Appears to be a final stage mineral, showing a chemical change in formation of epidote.

Test used in identification of the mineral species: 
     color, association, optical properties, blowpipe tests

Description of mineral species 5: CHABAZITE
     Occurs with epidote in "eye pods".  Only present in vugs in massive epidote where larger epidote crystals formed.  Appears as tiny rhomb shaped crystals in druz form.

Test used in identification of the mineral species: 
     Chemical (acid test), association, optical properties

Description of mineral species 6: PYRITE
     Occurs as both crystals and as a metallic film coating amphibolite crystals.  Some nice crystals as cubes in vugs in amphibolite.  Also, associated with chalcopyrite.

Test used in identification of the mineral species: 
     Chemical (acid test), blowpipe tests, crystal form

Description of mineral species 7: CHALCOPYRITE
     Occurs in vugs in massive pyrite as tiny wedge shaped crystals.  Often exhibiting a brightly colored tarnish.

Test used in identification of the mineral species: 
      Chemical (acid test), blowpipe tests, crystal form

Description of mineral species 8: TOURMALINE (Dravite)
     Occurs as acicular striated prisms, black to brown in color, occurs with quartz in "eye pods" and in laminar stringers within the amphibolite.

Test used in identification of the mineral species: 
     Crystal form, optical properties, EDS (Excalibur Mineral Co.)

[Link to Chemical and Instrumental analysis of this mineral]

Description of mineral species 9: PREHNITE
     Occurs as barrel shaped nodules in pyrite and chalcopyrite lined vugs with amphibolite and quartz.  Nodules are translucent and chatoyant.

Test used in identification of the mineral species: 
      Chemical (acid test), optical properties, crystal form

Description of mineral species 10: KAOLINITE
     Occurs as pods and lenses inter bedded with the amphibolite.  Some quartz grains scattered within the kaolinite.  Possibly altered feldspar.

Test used in identification of the mineral species: 
     Optical properties, physical characteristics

Description of mineral species 11: SULPHUR
     occurs as pale yellow "melted" crystals scattered on corroded pyrite.  Located in vugs in iron stained quartz.  As a lens in the fine grained amphibolite.

Test used in identification of the mineral species: 
     Chemical (acid test), blowpipe tests

Description of mineral species 12: CALCITE
     Occurs with pyrite and chalcopyrite in quartz veins within the amphibolite.  Calcite has a golden color.  Crystal habit is simple rhombs.

Test used in identification of the mineral species: 
     Chemical (acid test), crystal form

Description of mineral species 13: CHLORITE
     Occurs as greenish/tan velvety coating on chalcopyrite in vugs within massive pyrite.  Also occurs with prehnite.

Test used in identification of the mineral species: 
     Optical properties, physical characteristics

Description of mineral species 14: GARNET (var. Almandine)
     Occurs as rough to well formed dark red crystals with quartz.  Only one occurrence at location "A".

Test used in identification of the mineral species: 
     Crystal form, optical properties

Description of mineral species 15: HYALITE OPAL
     Occurs as coatings on fracture surfaces in quartz lenses in the amphibolite of location "A".  Mineral is fluorescent in S/W ultraviolet (bright green).

Test used in identification of the mineral species: 
     optical properties
 



[GMHP Protocol Page #6] 
Mineral Analytical Data for project # GWINNETT-01 Date: 4/2000

[Link to instrumental analysis data.]
EDS (Excalibur Mineral Co.)

[GMHP Protocol Page #6A] 
Mineral Analytical Data for project # GWINNETT-01 Date: 4/2000

PIEMONTITE
Borax bead test for manganese-Violet red (hot) in oxidizing flame, near colorless in reducing flame.
Associated with Epidote
Strong red pleochroism
Hardness between 6 and 7

EPIDOTE
Crystal form
Color - pistachio green
Strong pleochroism yellow to green
Hardness between 6 and 7

TOURMALINE (Dravite)
Crystal form
Strong pleochroism yellow to brown
Hardness 7

SULFUR
Crystal form
Color
Blowpipe charcoal block test (blue flame with sulfur dioxide generated)
Associated with pyrite

CHALCOPYRITE
Crystal form
Color
Hardness between 3 and 4
Blowpipe charcoal block test (blue flame) Note, this was difficult due to the small amounts of material available

[GMHP Protocol Page #6B] 
Mineral Analytical Data for project # GWINNETT-01 Date: 4/2000

PYRITE
Crystal form
Color
Hardness 6
Blowpipe charcoal block test yields magnetic globule with sulfurous fumes.

CALCITE
Crystal form
Effervescence in cold HCL
Hardness 3

PREHNITE
Color and appearance (optical characteristics)
Hardness 6
Dissolves slowly in HCL

GARNET
Crystal form
Color
Hardness between 6 and 7

CHABAZITE
Crystal form
Hardness between 4 and 5
Dissolves in HCL with a slimy residue

[GMHP Protocol Page #6C] 
Mineral Analytical Data for project # GWINNETT-01 Date: 4/2000

KAOLINITE
Color and appearance - See note.
Associations
Clay like feel to the material

HYALITE OPAL
Appearance
Optical characteristics
Fluorescence in U.V.

CLINOZOISITE (Possibly Zoisite)
Pale green block crystals, not like those of Epidote.
Association with Epidote and Hornblende
Hardness between 6 and 7

NOTE:  The presence of quartz in this material would seem to indicate an alteration product of Feldspar, possibly from and original material of granitic composition.



[GMHP Protocol Page #7]
Site Additional Data for project # GWINNETT-01 Date: 4/2000

[Link to site photographs.]
[Link to specimen photographs.]



[GMHP Protocol Page #8] 
Bibliography for project # GWINNETT-01 Date: 4/2000

LATEST THINKING ON THE STRATIGRAPHY OF SELECTED AREAS IN GEORGIA
WIGLEY, P.B.
GEORGIA GEOLOGIC SURVEY, 1981

GEOLOGY OF THE GREATER ATLANTA REGION
McCONNELL AND ABRAMS
GEORGIA GEOLOGIC SURVEY-BULLETIN 92, 1984

MINERALS OF GEORGIA
COOK, R.B.
GEORGIA GEOLOGIC SURVEY-BULLETIN 92, 1978

DANA'S TEXTBOOK OF MINERALOGY
FORD, W.E.
JOHN WILEY & SONS, NY, 1966
 

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