Above (left): Willemite
and calcite from Sterling Hill. Photo taken
in normal light.
The willemite occurs as pinkish to
tan, rough crystal
grains up to 1 cm across, in a matrix of white calcite. This material
was
abundant at the Sterling Hill mine, but even the seasoned collector
finds it
hard to resist picking up a few pieces here and there, thanks to its
striking
fluorescence in short-wave ultraviolet.
I'm pretty sure I took these two pictures with a 35mm camera and
Shop-Rite film. I don't think it was a digital I used.
Serious photographers used to get all bent out of shape when I told
them what brand of film I used in the 35. Then again, I never
claimed to be a serious photographer.
The biggest problem when using the 35mm to photograph the minerals was lighting.
No such thing as white balance! Usually the pictures came out
looking too yellow.
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Above (right): The
same specimen photographed in short-wave UV
light.
Note the pinkish fluorescence of the
calcite. The filter
of my old Mineralight made the calcite glow this peculiar color. The
Raytech
and newer lamps tend to make the calcite glow more of an orange-red
color,
which is more what I'm used to seeing. I remember talking to Nick
Zipco one day years back and he told me the same thing-- he noticed the
newer lamps made the calcite glow more of an orange-red. I wasn't
sure if he liked that fact or not. He did have an old Mineralight
for sale one day, just like mine, which I should have bought. I
do wish I could get this pink color back, but now I don't have any
lamps that bring it out.
I think these newer lamps use Hoya
filters. I'm not sure what brand was used in the old Mineralight
filter. It was
badly solarized when I got it, so pretty much the only thing that
showed up
well was... willemite and calcite. |