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Bok Asbestos Mine, Hollofield, Baltimore County, Maryland, USAi
Regional Level Types
Bok Asbestos MineMine
HollofieldUnincorporated Area
Baltimore CountyCounty
MarylandState
USACountry

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Latitude & Longitude (WGS84):
39° 19' 5'' North , 76° 47' 17'' West
Latitude & Longitude (decimal):
39.31806,-76.78806
GeoHash:
G#: dqcrstssk
GRN:
N27W43
Type:
Mine
Köppen climate type:
Cfa : Humid subtropical climate
Nearest Settlements:
PlacePopulationDistance
Milford Mill29,042 (2011)3.7km
Woodlawn37,879 (2011)5.2km
Randallstown32,430 (2011)5.5km
Ellicott City65,834 (2011)5.7km
Lochearn25,333 (2011)6.2km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Central Maryland Rock and Mineral Collectors ExchangeElkridge, Maryland13km
Baltimore Mineral SocietyBaltimore, Maryland15km
Chesapeake Gem & Mineral SocietyBaltimore, Maryland15km
Gem Cutters Guild of Baltimore, Inc.Baltimore, Maryland15km
Gem, Lapidary, and Mineral Society of Montgomery County, MD., Inc.Rockville, Maryland41km
Mindat Locality ID:
42106
Long-form identifier:
mindat:1:2:42106:6
GUID (UUID V4):
0


In partially amphibolized layered gabbro and pyroxenite. Rock is part of the Baltimore Mafic Complex. Bernstein reports anthophyllite fibers up to 15 cm long recoverable from the old dumps.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.


Mineral List


5 valid minerals.

Detailed Mineral List:

ⓘ Actinolite
Formula: ◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘ Anthophyllite
Formula: ◻{Mg2}{Mg5}(Si8O22)(OH)2
References:
USGS Bull 1082K
ⓘ 'Chlorite Group'
References:
USGS Bull 1082K
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Talc
Formula: Mg3Si4O10(OH)2
References:
USGS Bull 1082K
ⓘ Tremolite
Formula: ◻Ca2Mg5(Si8O22)(OH)2

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
Group 9 - Silicates
ⓘAnthophyllite9.DD.05◻{Mg2}{Mg5}(Si8O22)(OH)2
ⓘActinolite9.DE.10◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘTremolite9.DE.10◻Ca2Mg5(Si8O22)(OH)2
ⓘTalc9.EC.05Mg3Si4O10(OH)2
Unclassified
ⓘ'Chlorite Group'-

List of minerals for each chemical element

HHydrogen
Hⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Hⓘ Anthophyllite◻{Mg2}{Mg5}(Si8O22)(OH)2
Hⓘ TalcMg3Si4O10(OH)2
Hⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
OOxygen
Oⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Oⓘ Anthophyllite◻{Mg2}{Mg5}(Si8O22)(OH)2
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ TalcMg3Si4O10(OH)2
Oⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
MgMagnesium
Mgⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Mgⓘ Anthophyllite◻{Mg2}{Mg5}(Si8O22)(OH)2
Mgⓘ TalcMg3Si4O10(OH)2
Mgⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
SiSilicon
Siⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Siⓘ Anthophyllite◻{Mg2}{Mg5}(Si8O22)(OH)2
Siⓘ TalcMg3Si4O10(OH)2
Siⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
CaCalcium
Caⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Caⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
FeIron
Feⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Feⓘ MagnetiteFe2+Fe23+O4

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

Pearre, N. & A. V. Heyl (1960) Mineral deposits in serpentine rocks of the Piedmont Upland, Maryland, Pennsylvania and Delaware: U. S. Geological Survey: Bulletin 1082K: 707-833.
Bernstein, Lawrence R. (1980) Minerals of the Washington, D.C. Area - Issue 5 of Educational series, Maryland Geological Survey. Department of Natural Resources, Maryland Geological Survey. p.1-148.
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