Oregon Sunstone
Oregon Sunstone is a trade name for a particular type of labradorite, which belongs to the enormous mineral family of feldspars. Like common sunstone, it comes in various colors, including red, blue, green, yellow and most commonly, a faint straw color. Unlike common sunstone, Oregon Sunstone is transparent, and can be cut into amazingly lively faceted gems.
An oddity of Oregon Sunstone, which it shares with other labradorites, is the enhancing presence of schiller. In the case of Oregon Sunstone, schiller consists of thin, opaque, parallel sheets of copper within the gemstone. These sheets are so thin that they cannot be seen from the edge. When viewed from an angle perpendicular to the schiller plane, the schiller acts like a polished copper mirror, reflecting the coppery color back to the eye.
Schillered Oregon Sunstone is more valuable than Oregon Sunstone without schiller. A properly cut Oregon Sunstone with schiller maintains brilliance from every viewing angle, but displays a fascinating color shifting effect as the copper schiller is rotated into view. The stone does not actually change colors, the schiller merely has more or less effect on the appearance of the stone, depending on the viewing angle.
This means that schillered Oregon Sunstones are more desirable than those without schiller. Schiller is an inclusion, so included Oregon Sunstones are more desirable than perfectly clear ones. This presents a certain difficulty in grading the clarity of an Oregon Sunstone, since it is impossible to grant a VS or better clarity grade to a stone with obvious inclusions of schiller.
We are working on that problem, but for now, we are simply selling stones that would be VS or better if it were not for the schiller inclusions. We are grading them simply as SI (slightly included) and noting the amount of schiller visible in each stone. Schiller is noted on a scale of Strong, Moderate, or Weak, to indicate the effect of the schiller on the apparent color of the stone.
An oddity of Oregon Sunstone, which it shares with other labradorites, is the enhancing presence of schiller. In the case of Oregon Sunstone, schiller consists of thin, opaque, parallel sheets of copper within the gemstone. These sheets are so thin that they cannot be seen from the edge. When viewed from an angle perpendicular to the schiller plane, the schiller acts like a polished copper mirror, reflecting the coppery color back to the eye.
Schillered Oregon Sunstone is more valuable than Oregon Sunstone without schiller. A properly cut Oregon Sunstone with schiller maintains brilliance from every viewing angle, but displays a fascinating color shifting effect as the copper schiller is rotated into view. The stone does not actually change colors, the schiller merely has more or less effect on the appearance of the stone, depending on the viewing angle.
This means that schillered Oregon Sunstones are more desirable than those without schiller. Schiller is an inclusion, so included Oregon Sunstones are more desirable than perfectly clear ones. This presents a certain difficulty in grading the clarity of an Oregon Sunstone, since it is impossible to grant a VS or better clarity grade to a stone with obvious inclusions of schiller.
We are working on that problem, but for now, we are simply selling stones that would be VS or better if it were not for the schiller inclusions. We are grading them simply as SI (slightly included) and noting the amount of schiller visible in each stone. Schiller is noted on a scale of Strong, Moderate, or Weak, to indicate the effect of the schiller on the apparent color of the stone.
