The 2002 Season at the Orchard Mine
Apatites, quartz crystals and microclines April 2002
|. April 2002.
We have invested 15 days of mining in our attempts to shed light on what the pegmatite is doing and of course find the hidden awesome gem beryl. Our results are mixed.
Taking a few benches off of the headwall has yielded more beryls and
rose quartz. Currently the 60' test boring, that encountered pegmatite
its entire depth, is just 2' behind the wall. We have removed a small portion
of the pegamtite to the east of this bore hole and it appears that
the core zone is descending deeper as the pegmatite deepens.
Our work has shown that the apatites, which we continue to find, are most abundant in the portions of the pegmatite that are undergoing a displacement and not nearly as abundant when the vein settles down in an unperturbed path. Last Fall we encountered excellent prismatic manganoan-apatites where the pegmatite was first being displaced towards the footwall. Again we are finding well developed apatites as the pegmatite curves back into country rock channel on the eastern end of the schist zenolith. In addition, the pegmatite is making pockets in these disturbed areas. Depicted at the right, a well developed apatite 1 cm long sits on albite. What these apatites lack in color they compensate for in form.
As we removed more of the schist xenolith, we were surprised see the
extent to which it is permeated by feldspar and quartz stringers. At times
I doubted we were even drilling schist. Our goal has been to remove this
schist as quickly as possible for we considered to be only nuisance rock.
As we mucked out at the end of this tedious work, we were to receive a
pleasant surprise (for a change). As Richard bailed the schist muck down
into the lower pit in order make a road for our NEW 1973 Mack dump truck
to come up to this upper level , I watched the digging in hopes of seeing
something of interest in the spoil. As Richard removed the broken
schist from the hanging wall side, a large stringer emerged. With the schist
gone, a large pocket wall plate dropped out onto the pit floor.
The walls of this pocket were lined with microclines and albites with the occasional quartz crystal. See jpeg above . The albites, if that is indeed what they are, are the size of golf balls and are white and translucent. The crystals are unetched...a rarity for the Orchard. A possible new mineral for the Orchard was also in this pocket. Some of the crystal plates appear to have epidote. These crystals are on both sides of the plates. Well developed and terminated mm sized epidote(?) crystals occur in the spaces between the albites and microclines on the front. Finding this pocket was a surprise and these stringers now will be more closely examined. Perhaps, if they occur adjacent to a zone enriched in beryl, something akin to a Pakistani type beryl plate may be found. ....beryls standing unetched on microclines and albites.........mmm what the hay...throw in a few well formed schorls.
Another interesting occurrence of quartz and feldspar of appreciable dimensions is emerging to the right of the hanging wall and well within the country rock. This mini pegmatite is about 20' long and as much as 5' thick. Its eastern extent is unknown at this time.
An appealing speculation by some credible observers is, that as we mine to a point adjacent to the Bennett Mine, and since both pegmatites are in the same hill, the Orchard mineralization may take on more complex characteristics. Unfortunately there are no zoning laws in pegmatite land. A chemically impoverished pegamtite can take up residence next to its better heeled neighbor. So far the Orchard's ship hasn't come in and has stubbornly remained mired in the beryl-columbite-apatite classification. The size of the Bennett pegmatite dwarfs the Orchard as well. Perhaps a factor of 10 separates them. Another hope is the Orchard may broaden as well. Perhaps these stringers are hinting at something.
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