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Mark Heintzelman's mindat.org home page

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zzzzzzzzz . . . Eliza and Daddy Lazing on a Sunday Afternoon

Mark R. Heintzelman

Verified Account
Registered member since 18th Jan 2004

Mark Heintzelman has uploaded:
300 Specimen Photos
5 Locality Photos
2 Other Photos
 
World-wide systematic mineral collector since 1978, mindat contributer since Jan. 2004, focused on the mineralogy of Pennsylvania.

Now with the new and improved Mindat gallery, I've finally decided to contribute specimen pics from my other locality collections and world wide systematics, for localities which could use some additional representation. You can still view ONLY the Pennsylvania specimens by choosing the 'Mineral Name/Photo Title' option under 'Which Order' and typing "Pennsylvania" in the 'Keyword Box'. MRH

Messaging Statistics

Total messages posted:2,200
New threads started:69
First message posted:13th May 2007
Latest message posted:24th Aug 2026

Latest Discussions and Replies

Mar 2026All Delaware County Andalusites are actually Kyanite pseudomorphsPosted by Mark Heintzelman. 11 replies in Photos.Oct 2025Specimen not from Lancaster Co., Pennsylvania.Posted by Mark Heintzelman. 3 replies in Photos.Sep 2024More likely Mcguinnessite rather than NakauriitePosted by Mark Heintzelman. 2 replies in Photos.Sep 2023Fluorite image: Color profile damaged or over saturatedPosted by Mark Heintzelman in Photos.Feb 2023🦟 BUG: Discussion Groups - Can we no longer access posts pre 2021?Posted by Mark Heintzelman. 4 replies in General.Jan 2023Canadian experts needed, Old South Ham specimen?Posted by Mark Heintzelman. 6 replies in General.Jan 2023<a href="/min-8110.html" style="-webkit-user-select: text;">Imperial Topaz</a>Posted by Mark Heintzelman. 60 replies in Minerals.Nov 2022Wondering it this image should be made "User Only"Posted by Mark Heintzelman. 2 replies in Photos.Nov 2022Should we enforce boundaries over first identified mineral on images? Ex: Fluorite or CalcitePosted by Mark Heintzelman. 12 replies in Photos.Nov 2022Classic association at Cornwall Mine, PA is Pyrite, not ChalcopyritePosted by Mark Heintzelman. 13 replies in Photos.Oct 2022Specimen not from Cedar Hill Quarry.Posted by Mark Heintzelman. 10 replies in Photos.Sep 2022<a href="/loc-6909.html" style="-webkit-user-select: text;">Hyatt Mine, Talcville, St. Lawrence Co., New York, USA</a>Posted by Mark Heintzelman. 7 replies in Localities.Jul 2022Archived Strunz 8th seems to be missing True Zeolite - Mordenite GroupPosted by Mark Heintzelman. One reply in Improving Mindat.org.Jun 2022Lime Crest Quarry, NJ some locality string issues/inconsistenciesPosted by Mark Heintzelman. 16 replies in Improving Mindat.org.Mar 2022Is it appropriate to attribute an erratic (railway bedding stone) to the locality it was found?Posted by Mark Heintzelman. 8 replies in Photos.Feb 2022Need locality help from Midwest U.S. experts on this old mislabeled specimenPosted by Mark Heintzelman. 11 replies in Identity Help.Feb 2022Species I.D. entry needs correctingPosted by Mark Heintzelman. One reply in Photos.Jan 2022Celestine specimen is not from Bell's Mill Posted by Mark Heintzelman. 3 replies in Photos.Jan 2022Photo titled vanadinite, with no vanadinite present in the photo.Posted by Mark Heintzelman. 2 replies in Photos.Jan 2022Photo with damaged color profile?Posted by Mark Heintzelman. One reply in Photos.

 
 
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