We were enjoying the mild and sunny early fall weather during my visit to north west New Jersey, where my USA home base is located. My friends John Nipper and Denis Rogers took a trip to the abandoned Williams quarry, which is along the beautiful Delaware river.
This quarry exposed part of Chestnut Hill which is part of the Reading Prong, a formation of Precambrian Grenvillian rock which extends south east into Pennsylvannia. It is interesting geology since there has been uraninite in a serpentine matrix found there. This is an unusual association. The rock was quarried for a Verde Antique serpentine. The serpentinite is has high quality serpentine with tremolite, talc and chrysotile.
To the south end of this quarry there is a type of syentite pegmatite. The pegmatite is a strange color. A feldspar with a reddish almost purplish color with dark green minerals. In this was found thorianite and some of the interesting radioactive minerals by another collector I met there once.
I would have liked to have a scintillometer or Geiger counter. But I didn’t, so I looked for traces of thorium or uranium colorations, which are usually green, or orange. I took a chance and climbed up this pile of fallen boulders. I noticed some veins in a granitic or syenitic rock. It started to get interesting when I saw veins with quartz. There appeared some euhedral quartz crystals with chlorite and these veins showed potential. But alas, since I was in a precarious position hanging on the side of steep boulder cliff and balancing while chiseling hard rock, I didn’t think it was worth getting hurt smashing my hand again or falling onto the rocks. Also I am squeamish about being in too much vegetation here since I did catch Lyme Disease from a tick a couple of years ago just on the other side of the River. I found a a few samples of quartz crystal and gave it up, but not without getting a little poison ivy.


Later we took a look along the bank of the Delaware River, because we noticed the whole slope after the road to the river seemed to be rock taken from the quarry.



John found this nice piece of the “deadly” chrysotile asbestos. (I made sure not to snort the dust). Then after combing the bottom of the slope I found some nice specimens of eastonite, a very colorful piece of serpentine (which I gave to John to carve) and other interesting minerals to be identified.













I brought back the a few interesting specimens which I am not sure about.
The first may be tourmaline. I found some rock that is a greenish color with black mineral and small cavities. Here is a zoom sequence:


The area of view in the 1st photo is 12mm and as I zoomed in the second is about 4mm with the opening less than 1mm and final zoom is a field area about 2mm. There are prismatic crystals with striations and a curved triangular cross section. The pink material in the vug looks like it could be calcite.
I broke up another rock which had cleavages of a pinkish-purplish feldspar. This particular piece had a vein in it. The first photo is again about 12mm or ½” field. The second shot is about 6mm or ¼” area. I am not sure what this mineral is, but it could be actinolite as a guess.


Another rock was a white rock with lots of small vugs. Looking closely at the crystals it seemed to be dolomite. Here is an 1 ½” x 1” pieces with cavities. Some of the cavities contained small pyrite cubes about 1mm.

In pieces of rock that came from the pegmatites I found these small titanite crystals. Some are altered a yellow color. First shot is of a piece about 2”x2” with a 1/8”x 3/8” brown crystal in a grayish feldspar matrix. Second is a 12 mm field view with a 2mm xl. Third is another 2mm titanite altered yellow.

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