Chantilly Prospect B

Occurrence in Fairfax county in Virginia, United States with commodities Copper, Silver
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Host and associated rocks
  8. Nearby scientific data
  9. Geologic structures
  10. Ore body information
  11. Controls for ore emplacement
  12. Economic information about the deposit and operations
  13. Mining district
  14. Land status
  15. Ownership information
  16. Links to other databases
  17. Bibliographic references
  18. General comments
  19. Reporter information

Geologic information

Identification information

Deposit ID 10067559
MRDS ID W000343
Record type Site
Current site name Chantilly Prospect B

Geographic coordinates

Geographic coordinates: -77.41552, 38.88364 (WGS84)
Elevation 110
Relative position 1.8 KM (1.1 MI) 5.50 DEG. E. OF CHANTILLY.

Site location context

Political divisions (FIPS codes)

Fairfax(county)

Virginia(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Herndon(quadrangle 1:24,000 scale)

Washington West(quadrangle 1:100,000 scale)

Washington(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Middle Potomac-Anacostia-Occoquan(hydrologic unit)

Potomac(hydrologic accounting unit)

Potomac(hydrologic subregion)

Mid Atlantic(hydrologic region)

Geographic areas

Country State County
United States Virginia Fairfax

Comments on the location information

  • IN EXCAVATION OF TRANSCONTINENTAL GAS PIPELINE CO., 50 M (150 FT) SE OF TABSCOTT RD. (STATE ROAD 4646) JUST NE OF JUNCTION WITH STATE ROAD 4648 (LEE'S CORNER ROAD), 0.4 KM (0.3 MI) BY ROAD SE OF JUNCTION WITH STATE ROAD 4951, 0.2 KM (0.2 MI) SW OF JUNCTION WITH U.S. HWY 50, 0.2 KM (0.1 MI) NW OF JUNCTION WITH STATE ROAD 645.

Commodities

Commodity Importance
Copper Primary
Silver Secondary

Comments on the commodity information

  • MALACHITE AND AZURITE WERE IDENTIFIED BY X-RAY ANALYSIS AND EXISTED ON LAMINAE AND JOINTS AS THIN COATINGS (0.8 MM THICK). ONE XL. OF CHALCOPYRITE WAS RECOVERED THROUGH HEAVY MINERAL SEPARATION OF A WHOLE ROCK SAMPLE.

Materials information

Materials Type of material
Malachite Ore
Barite Gangue
Pyrite Gangue

Analytical data

Result MINERALIZED ZONE: UPPER 3 FT: 5000 PPM CU, 10 PPM AG
Result LOWER 2 FT: 5000 PPM CU, 5 PPM AG
Result 2 FT MALACHITE-RICH ZONE: 20,000 PPM CU, 50 PPM AG
Result 1 FT MALACHITE-RICH ZONE: 10,000 PPM CU, 7 PPM AG
Result GRAB OF MIXED BEDROCK: 5000 PPM CU, 3 PPM AG (D'AGOSTINO AND HANSHAW, 1970).

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite > Diabase
    Rock unit name Diabase
    Rock description Diabase
    Stratigraphic age (youngest) Late Triassic
    Stratigraphic age (youngest) Late Triassic
    Stratigraphic age (youngest) Late Triassic
  • Host or associated Host
    Rock type Sedimentary Rock > Clastic Sedimentary Rock > Sandstone
    Rock unit name Diabase;Manassas Sandstone, Newark Group
    Rock description Diabase;Manassas Sandstone, Newark Group

Nearby scientific data

(1) -77.41552, 38.88364

Economic information

Geologic structures

Type of structure Regional
Structure description Ne-Sw Trend, Culpeper Triassic Basin ; Reg.Trends: Northeast-Southwest
Type of structure Local
Structure description Some Faults Cut Across The Diabase Near Chantilly According To The State Map. Drake And Froelich (1977) Indicate Several Faults In The Vicinity Of Chantilly.

Ore body information

  • General form LINEAR
    Thickness 1.5M
    Depth to top 0M
    Depth to bottom 1.5M

Controls for ore emplacement

  • Bedding Planes, Joints, Fractures

Comments on the geologic information

  • MAJOR.UNITS: SANDSTONE AND DIABASE ; GEOL.DESC: CU MINERALIZATION IN TRIASSIC OF EASTERN U. S. USUALLY SUGGESTS PARTIAL CONTROL OF PRIMARY ORE MINERALS BY FAULTS AT THIS LOCALE, HOWEVER, ONLY SUPERGENE MINERALS OCCUR, DEPOSITED MAINLY ALONG BEDDING PLANES. ; REG.COM: SCHIST AND PHYLLITE OF UNKNOWN AGE UNDERLIE THE TRIASSIC SEDIMENTS.

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic
Deposit size Small
Significant No
Discovery year 1968
Discoverer P. Hanshaw And J. Owens

Mining district

District name Culpeper Basin

Land status

Ownership category Private

Ownership information

  • Type Owner
    Owner Transcontinental Gas Pipeline Co.

Comments on the reserve resource information

  • THE SURFICIAL MALACHITE ZONE COULD NOT BE TRACED VERY FAR SO IT IS NOT POSSIBLE TO ACCURATELY ESTIMATE THE RESERVES.

Comments on development

  • ECON.COM: THIS IS ONLY AN OCCURRENCE IN AN URBANIZED AREA, AND THEREFORE IT IS DOUBTFUL IF IT WOULD EVER BE MINED.

Reference information

Bibliographic references

General comments

Subject category Comment text
Deposit THE MALACHITE WAS NOTED ONLY IN THE TRENCH AND COULD NOT BE TRACED, THEREFORE LITTLE IS KNOWN ABOUT THE DIMENSIONS AND ATTITUDE OF THE DEPOSIT.
Deposit THE MALACHITE BEARING SANDSTONE WAS NOTED OCT. 1968 IN A TRENCH EXCAVATION OF THE TRANSCONTINENTAL GAS PIPELINE CO. NO NAME WAS PREVIOUSLY APPLIED TO THIS OCCURRENCE. CHANTILLY PROSPECT "A" IS LOCATED 0.8 KM TO THE NNW. ; INFO.SRC : 1 PUB LIT; 2 UNPUB REPT

Reporter information

Type Date Name Affiliation Comment
Reporter 01-MAR-1972 Meintzer, Robert E. (Le Van, D.C.) Virginia Division of Mineral Resources
Updater 01-JUL-1987 Sweet, Palmer C. Virginia Division of Mineral Resources

Beyond USGS

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