Bumblebee Agate (sometimes called Bumblebee Jasper) has been known only since the late 1990s and has been found only on the Indonesian island of Java. It is not really agate or jasper but a mix of minerals in a matrix of a volcanic material mined from sulfur vents. It is composed of anhydrite (gypsum), sulfur and hematite in a matrix of volcanic tuff (welded ash). It may also contain plumose calcite and ilmenite.
This is perhaps the rarest color here…Exquisitely colored a rich citrine, burnt yellow color, this matrix specimen of prismatic, nearly equant, quartz crystals is very impactful. They are glassy, and translucent, with the largest crystal reaching 3.5 cm in length.