On a December Sunday that had "work around the house" written all over it, I decided to tackle a job I had put off for over a year. It was time to install roof-heating cables that I had purchased before my contempt for extension ladders had gelled. A smoldering disdain for ladders began years ago when I lost control of my 32-foot ladder while moving it, fully extended and upright. I watched, helpless, as it "timbered" just past telephone wires and onto my wife’s poor Toyota, bouncing next onto an azalea bush, which split neatly in half. (For some reason I think of both biblical miracles and Robin Hood when I recall this event.) Whatever the symbolism, I did not learn my lesson, and this December I dropped my ladder again, this time through my son’s bedroom window. The only cure for this non-elevating experience was to go collecting.

It was early afternoon by this time, so I could not travel far. I scooted over to a Dracut, MA locality that had on occasion yielded zeolite microminerals, pale prehnite plates, quartz and sulfides. Hiking in, I drew suspicious stares from dirt bikers zooming up and down the quarry roads, and I briefly considered hitching a ride to maximize collecting time. The northwest area of the quarry had been recently blasted, so I walked the wall of a wide semicircular notch that had been cut roughly northward. I found a vein of massive pale yellow prehnite that widened to contain vugs of low prehnite blades. I had seen this scaly prehnite before, but these vugs sported glistening colorless needles of something different, to be ID’ed later.

Further along this cut, I found a vein of vuggy, almost colorless, prehnite with Roman sword-shaped terminations. It hardly resembled the green balls of prehnite from Connecticut Valley traprock quarries. Perched on knobs of prehnite were frosted or snow-white rods of stilbite to 13 mm long. Most of the stilbites were packed in a jackstraw arrangement on the prehnite knobs, but some assumed bow tie habits. A few damaged knobs revealed a core composed of a single quartz crystal that apparently came earliest in this paragenesis: quartz, prehnite, then stilbite.

This vein was widest about 6 feet above the top of a debris pile, just within my reach. The largest plate of stilbite (20 x 20 cm) was on the side of a 50-lb. block of loose wall rock. I was able to pry this out and into my arms with the aid of a sturdy pine bough (I didn’t bring a pry bar). I was pleased to guide this block to the ground right side up, then chiseled off large plates. The vein extended up and into the wall, beyond my reach. I briefly wished for an extension ladder, then came to my senses and called it a day. Miraculously, there was just enough material to fill my carrying bags to the brims when wrapped with every last sheet of newspaper I had packed in. The hike out felt good.

At home, it took intensive ultrasonic cleaning to coax off the stubborn pocket clay, but good stilbite was revealed. Under the ‘scope, the glistening microcrystals from the other side of the cut turned out to be stilbite as well, lustrous and gemmy. It is intriguing to imagine that somehow these two prehnite veins in close proximity sported different habits of stilbite. This is the third zeolite I have recovered from this locality, along with heulandite and chabazite, and so far is the largest. I have clearly done better standing on solid ground than on ladder rungs.

Paul Gilmore

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