"Barf Datolite"


On an unseasonably warm day in January, 2001, I traveled alone to my favorite traprock quarry and had the place to myself. I had previously shared in the harvesting of calcite, prehnite, and babingtonite from my first pocket ever, anywhere, at this locality. I had hoped to visit it again with same team, but my partners were unavailable, so I had the perfect excuse for highgrading. The pocket we emptied had been erased by subsequent blasting. The new wall had minimal calcite and prehnite showing so I began a circumnavigation of the quarry.
A couple hundred yards away, I opened a vein of small dogtooth calcites (blah). Further along I noted the contact of local redbed sandstone beneath the lava flow that buried it and made this basalt deposit in Triassic times. Along the contact were tiny vugs of bright blue-green copper secondary minerals, the copper having leached from the sedimentary rock that bore viable copper ore mines elsewhere in the valley. These tiny vugs were more numerous within paler grey volcanic rock that formed a roughly fifty foot transition zone between the contact and the typical darker basalt. I wondered if this zone was lighter because of a higher silica content (rhyolite), also leached from the sandstone contact.

The igneous rock here is bedded here, and slabs are spalling off, forming a shelf angled to about 25 degrees, just flat enough to climb. Atop this shelf I pried out a chunk of wall rock, revealing a large vug of quartz and calcite. The 1/4 to 1/2 inch quartz crystals had golden needle inclusions that I excitedly designated rutile, but were later identified as goethite. The quartz had a cool habit that looked like scepters, with tiny crystals growing perpendicular to the shaft, like ears of corn. The 3/8 inch calcite rhombs were gemmy and pale yellow, but dinged. The tiny vugs of copper secondaries contained bright aqua micro balls and needles resembling chrysocola.

Carrying some of this booty down the steep shelf, I lost my footing, falling on my butt. Strangely, just as I hit the ground nausea wafted through me, the vanguard of sinister complications later in the day. I stashed this load of specimens near the middle of the quarry and headed to its southern end.

I found a fresh blast pile with an interesting bright vein traversing the wall above. Up close the vein was massive datolite with palm sized vugs. One vug pried from the wall had a triangular shape with flat bottom, perfect for display. Other boulders strewn through the blast pile showed vug corners that were liberated mostly intact. The datolite crystals were incredibly lustrous, pale green, to 1 inch in size. One cathedral shaped vug could not be removed intact, and remained in situ for over a year.

!Caution: blatant brag approaching!

If there is nicer datolite somewhere in this country, I'd like to know where. Some vugs were bordered by amethyst that appeared purple only on fractured edges, but grey on crystal faces. Some vugs also contained satin lustered calcite crystals to 1 1/4 inches, or quartz coated with a lipstick-colored hematite dust. One large boulder sported a calcite and datolite vug, but was clearly too large to carry out. A single mighty whack of my hammer (with breath held) split the rock in two, exposing an unexpected vug of calcite in two habits: lustrous gemmy golden rhombs over quartz, and a frosted "ice cube", nestled among psilomelane-included quartz. This head-sized specimen thus shows datolite on one side, and calcite and quartz on the opposite side, and is thus rotated every so often on my desk. There was a time when I would have split it further to have two separate specimens, but after about 100 bad trimming experiences, I have learned my lesson, and let it be.

At about this time I got a bad feeling in the pit of my stomach, literally. I wrapped my specimens in my shirt (shame on me for not bringing enough newspaper) and began a trek across the quarry to my original stash. My intestinal tract then proclaimed its own agenda with a full range of impending events.

The holiday party I attended 48 hours before had left me with an unexpected gift: gastroenteritis that eventually affected 75% of partygoers. By the time I reached my stash with an overwhelming load of specimens, I knew I would be lucky to leave with the contents of my stomach, let alone my specimens. I managed to hide several nice datolites under old oil drums for later retrieval, and tried to hike out to my car. As matters worsened, I resorted to a special ops rescue by cell-phoning my sister (who lived nearby) and requesting urgent extraction. She met me at a clandestine location and ferried me to my car.

It was longest drive home I have yet experienced, with visits to every rest stop on the turnpike. I have vague memories of well maintained service station lawns, viewed close up. Oddly, I ran into a fellow collector and his wife at one of these rest stops, at least I think I did, if it was not a hallucination. I presented him with a datolite crystal so he could bear witness to my successful collecting, should I fail to make it home. Miraculously, my GI tract settled down during an infuriating traffic jam on I-290 near Worcester. Obviously, I survived to tell this harrowing tale.

Epilogue:

Some months later, two members of my collecting team located my stashed datolites and carried them out for me. To this day, I get a little queasy when I look at specimens from the "Barf Pocket" of 2001.

Paul Gilmore

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