Oxford County, Maine
Coromoto Minerals
The 2003 Season at the Orchard
Mine
---- May -----
3 cm etched beryl
Coromoto Minerals
The 2003 Season at the Orchard
Mine
---- May -----
3 cm etched beryl
In May we got down to some serious mining at the Orchard. As we worked
another 6' along strike, the very blocky mineralization appeared to give
way to a new expression of mineral concentrations at the Orchard. The Orchard
pegmatite, most likely an LCT beryl columbite/phosphate peg, is very poor
in muscovite and tourmaline (schorl). Only at the contacts do we see biotite
laths to 50 cm and a few schorls. The first tip that something was afoot
was the  increasing
abundance of gray apatites in pockets more centrally located within the
pegmatite. These apatites were emplaced on quartz and feldspar and ,although
still gray, we becoming large. The other thing we noticed was the appearance
of more schorl within the this central portion as well. The next think
to get our eye was finding a small vug containing microclines with a halo
of small muscovites. Although this association may not rate a second glance
at other pegmatites, at the Orchard it was a rarity. Almost never before
have the muscovites presented in such as fashion. Very occasionally we
will find a vug or beryl cast that have a few loose muscovites. To our
recollection, never before have we seen them standing on microclines.
Little things .... may be adding up. Another observation was
beginning to take root. In 98-2000, the beryls in pockets were associated
with blue apatites. When the beryls in pockets disappeared, the apatites
turned gray. At first we did not make the connection but as the dry spell
persisted over 2 years of mining with a steady flow of gray apatites the
linkage was starting to become more compelling. I commented to Richard
that if we starting to see a color shift in the apatites, our prospects
of finding pocket beryl may start looking up.
This was not necessarily prescience on my part. I had already started
to notice a color change in the apatites. The small group below was the
first clue. This group was removed from a foot wall vug. Normally, the
foot wall is relatively beryl poor, so I was inclined to dismiss what I
was seeing. Only the inevitable semi bored chit-chat amongst miners, while
toiling, percolated this comment . We were to find below this area
etched beryl fragments in vugs. In addition, the Orchard seemed to
be bulging a little as the foot wall was at least 2 feet outside the contact
just 6 feet back up strike. The hanging wall side seemed to remained unchanged.
Shortly after this we found our first beryl in vug in 2 years. Although not very special, at least it was finally the real thing. Our next bench back into the headwall produced some more encouragement.
We opened a small albite lined pocket containing bertrandite, gemmy apatites
and some etched beryl. The beryl at the top of the page is one of these.
Below this area we found a cobalt blue apatite group in a small vug. The
color association of blue apatite was becoming more compelling. At the
same the blocky feldspar and quartz seen along the last 20' of strike at
this horizon was beginning to shift to a less crystallized texture. Did
the schorls in the headwall ahead mean that we were about to run headlong
into a severe pinch, or ,worse yet, the end of the pegmatite at this depth?
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