 A corner to work and study. Photo: E. Skalwold | |
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| A comfortable workspace is imperative and highly individual. For me that means an L-shaped working area with easy access to both microscopes, as well as all other oft-used instrumentation. The most frequently used refractometer is on a stand which brings it up to a comfortable working height. For those working with gemstones and concerned with grading color, especially that of diamonds, a neutral wall color is also a prerequisite. As that is not the case for me, the memories of eating my daily ration of tree-ripened mangos while living in Thailand were a much more seductive influence in this regard. Fine optics are central to inclusion study and gemology. I was a very lucky recipient of vintage Reichert 570 and 580 microscope pods which both fit in the desktop darkfield base, as well as in a portable lab. The 580 has a photoport for imaging, but both accept an ocular attachment for use with a lightweight camera. The Swiss-made Wild M400 microscope was once used for work on microchips, a base design which leaves plenty of room for setting up a fiberoptic cool darkfield and other types of stages. Both microscopes can be used with immersion cells and have auxiliary lenses which increase the magnification. The Wild M400 is also equipped with a Nikon D70 camera mount as seen here. For the study of minerals and gem materials, a darkfield base such as the GIA Gemolite Mark VII is nice to have, though developing expertise with fiberoptic illumination techniques opens a whole new world. With a selection of fiberoptic wands in a range of sizes including that of a pinpoint, one can control lighting far better and with extraordinary adaptability. These wands can be used with other illumination such as darkfield, brightfield, polarized, diffused, and monochromatic. One need only study the works of master-gemologist John Koivula to learn just how important fiberoptic lighting is to the science of gemology. The desktop spectroscope's fiberoptic pipe may also be used with the microscope, as well as with the handheld spectroscopes and dichroscope. Along with white light, it produces monochromatic blue, red, yellow and green which can be used alone or with various combinations of filters in diagnostic work. Most importantly, all must be protected from dust and salt air and should at least be covered when not in use. Sealed work cabinets in a dedicated room is ultimately the best protection, but not always possible..... | |
| So, off to the materials testing laboratory! | |
 Olympus IX50 Inverted Metallurgical Microscope. Photo: E. Skalwold | |
| The highly polished base of a maw-sit-sit cabochon was resting on the center of the stage; I removed it just before this picture was taken but the last view is still up on the screen. A similar view is shown below. | |
 Maw-sit-sit as seen through the above microscope. | |
| Moving between microscopes is like driving a stick-shift truck one day and the next climbing into an automatic sedan; one usually spends the first few minutes stomping around for the clutch. What I love about this instrument is the ability to move the stage around with just two knobs; it is like driving the lunar module, though in a verdant green landscape in this case. Maw-sit-sit is one of the most fascinating, lovely gem materials I can think of, especially under a microscope. |  A Leica MZ APO, very similiar to the Wild M400, but with these attachments, even more fun... Photo: E. Skalwold |
 Needles (probably rutile) in star smokey quartz from Brazil. | |
| These are the needles causing the star in the smokey quartz seen at the bottom of this page (see Asterism). They are so fine that they are barely visible with the naked eye and very hard to resolve even under a high power microscope such as this. They have an iridescent golden color and, as expected, there are three sets of needles oriented in a plane perpendicular to the c-axis of the cab. What I hoped to see was a good cross-section where a needle breaks the surface of the cabochon, but they are just too small. So, off to the next room and the instrument which has held my fascination ever since I was in highschool.... | |
 Scanning Electron Microscope. Photo: E. Skalwold | |
| Before being placed in the SEM, the specimens are first coated with a very thin layer of gold. Rushing does not pay off; the first pictures depicted vast mountain ranges of finger grease (confirmed by spectroscopy), but I'll find that cross-section - all bets are that it will be a square - more pictures coming soon! | |
 For more on this phenomenal stone, see Asterism Specimen courtesy of Rick Martin, Art Cut Gems. Photo: Rick Martin | |
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