Kaleidoscope Schiller How-to
based on a "found" gem

I was helping a jeweler friend recently with quality control on a parcel of commercially-cut Oregon Sunstone he was purchasing. As I examined the stones for color, presentation, and any flaws, one stone caught my attention. The gem was about 9mm in diameter, and the cutting was oriented about the schiller inclusions in a way that created a wonderful spider-web or vortex pattern when the stone faced-up. This is such a beautiful example of what we’ve come to label as “kaleidoscope schiller”, and the pattern is so symmetrical that I decided to share it here. You can see in the face-up photo how the pattern displays. (click photo for high-res image) The same stone, face-down, appears to be devoid of inclusions. Even in immersion oil, the stone appears clean. So, where’s the magic that makes the vortex? Dark-field lighting in oil shows that there is some schiller hiding in there... And, an oblique angle with careful lighting displays the thin planes of schiller. (click photo for high-res image) You can see that even with the schiller turned for maximum reflection, the planes are still quite thin, allowing lots of light through – like a tiny metallic cheese-cloth or mosquito-screen. In this near-profile view the schiller is still reflecting light, and it’s possible to see the multiple layers of inclusion lying almost parallel to the table. In the back-lit profile, the layers and their orientation become very clear. (click photo for high-res image) Each pavilion face is a mirror. So, when looking at the stone face-up, the actual view is through the mirror, looking ACROSS the pavilion at an edge-on view of the schiller planes. If you imagine a copper-colored cheese-cloth or mosquito-screen lying parallel to the table, it’s easy to imagine light passing through that layer, just as when looking out your window. However, each pavilion face turns the view 90 degrees, providing an edge-on view of the copper-colored screen. And, from that angle, it appears quite solid. The many pavilion faces, arranged in a cone-like shape, all reflect edge-on views of the many layers of schiller, resulting in the remarkable vortex-like kaleidoscopic effect: This is another example of why I think Oregon Sunstone is one of the greatest gem materials on the planet - and my personal favorite to work with.