KNOWLTON MINE
Greenland, Ontonagon Co., MI
August
5, 2003
Knowlton
Mine dump
On
Tuesday morning I had no trip scheduled, so I went to the Wal-Mart in Houghton
and bought a new digital camera. We also had to make a trip to Chassell to try
to get Barb’s sewing/embroidery machine repaired. We didn’t have much luck on
that score, though. The dealer couldn’t get the required parts before we would
head home.
On
Tuesday afternoon I headed south into Ontonagon County for the Knowlton mine.
It’s located on the left side of the road to the Caledonia mine, about 1.1
miles from the start of Caledonia Road. It may not be accessible at all times,
since there was a large boulder blocking the access trail two days after this
trip. GPS coordinates are Lat. 46 deg. 45.275’, Lon. –89 deg. 06.902’.
This
is a fairly small dump, and one I had never heard of before. The material I
collected didn’t look very promising when I picked it up, but after getting it
home it was very interesting. Most of the vugs are filled with calcite, and
after dissolving the calcite with hydrochloric acid (diluted about 1:1) and
rinsing thoroughly, the material was spectacular. Vugs lined with microcline
(var. adularia) also had epidote crystals and pumpellyite fibers on top of the
microcline. This makes very attractive micromounts. The microcline is red, and
the yellow-green epidote and pale green pumpellyite really stand out. I also
found white saponite in balls of platy crystals in some of these vugs. There are
also vugs lined with prehnite that has copper crystals on it. This material was
a very pleasant surprise.
On to the next field trip, the
Central Mine