Grasvally

Plant in South Africa with commodity Chromium
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Nearby scientific data
  8. Ore body information
  9. Economic information about the deposit and operations
  10. Mining district
  11. Ownership information
  12. Workings at the site
  13. Links to other databases
  14. Bibliographic references
  15. Reporter information

Geologic information

Identification information

Deposit ID 10134718
MRDS ID ISM0002
MAS/MILS ID 7910200041
Record type Site
Current site name Grasvally
Alternate or previous names Grasvally Mine
Related records 60000504

Geographic coordinates

Point of reference Ore Body
Geographic coordinates: 29.00143, -24.27998 (WGS84)
Elevation 1500
Location accuracy 10000(meters)

Site location context

Political divisions (FIPS codes)

South Africa(country)

Africa(continent)

Land(continent)

Geographic areas

Country
South Africa

Commodities

Commodity Importance
Chromium Critical Primary

Materials information

Materials Type of material
Chromite Unknown
Pyroxene Unknown

Nearby scientific data

Ore Body (1) 29.00143, -24.27998

Economic information

Ore body information

  • Strike N10E
    Dip 40W
    Thickness 1.05M
    Length 440M
    Width 305M
    Depth to top 183M
    Field Value
    MAS Matrix # 1
    MAS Column # 1
    Type of Orebody #1 STRATIFORM
    Shape of Orebody #1 TABULAR
    Primary mode of Origin MAGMATIC DIFFER
    Primary Ore Control IGNEOUS
    Secondary Ore Control LITHOLOGY
    Degree of Wallrock Alter. SLIGHT
    Strike And Dip N10E:40W
    Minimum Depth to Top 0
    Avg. Thick. Unconsol. Mat. 0
    Min. Thick. Unconsol. Mat. 0
    Date of Last Modification 930510

Comments on the geologic information

  • TYPE OF ORE BODY IS LAYERED INTRUSIVE.

Economic information about the deposit and operations

Operation type Underground
Development status Plant
Commodity type Metallic
Significant Yes
Discovery year 1960
Mining method Open Stope - Breast Stoping
Year of first production 1962
Plant type Beneficiation (Mill)
Plant subcategory Gravity
Milling method Gravity

Mining district

District name Potgietersrust District

Ownership information

  • Type Operator
    Owner Cromore Ltd.
    Home office South Africa
    Year 1989
  • Type Owner
    Owner Samancor
    Interest 100
    Home office South Africa
    Year 1989

Comments on the production information

  • Y-RECORD RECOVERY REPRESENTS INDIVIDUAL ETD MILL RECOVERIES. TOTAL 1/89 ETD RECOVERY IS 85.87%.
  • PRODUCT B ORE IS TRANSPORTED TO THE SMELTER AT WITBANK, SOUTH AFRICA. THE REMAINDER IS EXPORTED TO JAPAN.

Comments on the reserve resource information

  • 1/89 INSITU DEMO. TONNAGE= TO 610 M VERT. DEPTH FOR BOTH UPPER AND LOWER SEAMS. 100 PCT RECOV.ABOVE 366 M LEVEL,60 PCT BELOW.
  • COLUMNS 1 AND 2 ARE THE ESTIMATED IN-SITU RESOURCE AT THE 75% PROB. LEVEL. COL 1 REPRESENTS LESS THAN OR EQUAL TO 366 M OF DEPTH. COL 2 REPRESENTS LESS THAN OR EQUAL TO 610 M OF DEPTH. COLUMNS 3 AND 4 ARE THE ESTIMATED RECOVERABLE RESOURCE AT THE 75% PROB. LEVEL. ONCE AGAIN, COL 3 IS FOR A DEPTH LESS THAN 366 M, WHILE COL 4 IS FOR A DEPTH LESS THAN 610 M. THE RECOVERABLE FIGURES ASSUME 100% RECOVERY AND 0% DILUTION. ALL CALCULATIONS USE BOTH THE ZOETVELD 294KR AND GRASVALLEY 293KR FARMS.

Workings at the site

  • Type of workings Underground
    Overall depth 448M
    Field Value
    MAS Development Schedule # 1
    Mining Record # 1
    Status of Mining Method ESTIMATE
    Mining Method BREAST STOPING 10-30
    Percent Recovery 100
    Hardness of Rock HARDROCK WITH LITTLE WATER
    Rock Support Chars. SUPPORTING
    Mine Support Chars. POST, HEADBOARD, CAPS, ROOF BOLTS
    Number of Shafts 5
    Length of Inclines (m) 500
    Slope of Inclines 45
    Number of Inclines 3
    1st Condition of Workings OPEN
    Capacity 960
    Capacity Units MT ORE/DAY
    Unit Production Cost 35.64
    Units of Production $/MT ORE
    Operating Days per Year 250
    Operating Shifts per Day 2
    Year of Information 1989

Reference information

Bibliographic references

  • Deposit

    COAL,GOLD&BASE MINERALS OF SOUTH AFRICA. GRASVALLY THREE

  • Deposit

    YEARS ON.V.23,NO.10,DEC.1975,PP.35-36.

  • Deposit

    COAL,GOLD&BASE MINERALS OF SOUTH AFRICA.R8M EXPANSION

  • Deposit

    PROGRAMME FOR GRASVALLY CHROME MINE.OCT.1972;PP.39-45.

  • Deposit

    RANKIN,G.1975.CHROMIUM AND FERROCHROMIUM IN SOUTH AFRICA.

  • Deposit

    SAUNDERS AND TAYLOR,INC. INVESTMENT INDUSTRY REPORT.

  • Deposit

    JOHANNESBURG,S.A.PP.1-117.

  • Deposit

    SIEMS,P.1976.CHROMITE MINES AND RESOURCES IN THE REPUBLIC

  • Deposit

    OF S.AFRICA.MINERALS AVAIL.SYSTEM.DEC.1976.PP.21-23.

  • Deposit

    ANON. 1972 "RBM EXPANSION PROGRAMME FOR GRASVALLY CHROME

  • Deposit

    MINE" COAL, GOLD, AND BASE MINERALS OF SOUTHERN AFRICA

  • Deposit

    OCTOBER PP. 39-45

  • Deposit

    ANON. 1978 "MINING THE HIGH-GRADE CHROMITE OF SAMALOR'S

  • Deposit

    GRASVALLY" S.A. MINING & ENGINEERING JOURNAL MARCH 1978

  • Deposit

    BHATT, B., CHIST, E.M., SHEEHAN, L.E.,JR., AND SIEMS, P.L.

  • Deposit

    1976 "CHROMITE MINES AND RESOURCES IN THE REPUBLIC OF

  • Deposit

    SOUTH AFRICA" UNIVERSITY OF IDAHO FOR THE MINERALS

  • Deposit

    AVAILABILITY SYSTEM. U.S. BUREAU OF MINES. GRANT NUMBER

  • Deposit

    G0254014 DECEMBER

  • Deposit

    TEX REPORT, 1978.

  • Deposit

    SILK M H, 1988, "WORLD CHROMITE RESOUCES AND FERROCHROME

  • Deposit

    PRODUCTION", MINTEK SPECIAL PUBL. NO. 11.

  • Deposit

    DE VILLIERS, 1970, THE STRUCTURE AND PETROLOGY OF THE MAFIC

  • Deposit

    ROCKS OF THE BUSHVELD COMPLEX SOUTH OF POTGIETERSRUS:

  • Deposit

    GEOLOGICAL SOCIETY OF SOUTH AFRICA SPECIAL PUBLICATION

  • Deposit

    1, SYMPOSIUM ON THE BUSHVELD IGNIOUS COMPLEX AND OTHER

  • Deposit

    LAYERED INTRUSIONS, PP. 23-35.

  • Deposit

    DAVIDOFF R L, BOYLE E H JR, 1988, "NOTES FROM VISIT TO THE

  • Deposit

    REPUBLIC OF SOUTH AFRICA", USBM.

Reporter information

Type Date Name Affiliation Comment
Reporter 11-MAY-1993 Boyle, Ed U.S. Bureau of Mines

Beyond USGS

Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.