Stalactitic chalcedony geode "The Pie Chart"

Stalactitic chalcedony geode "The Pie Chart"Locale: Atlas Mountains, Morocco Approx dimensions: 4 x 4 x 3" Approx weight: 588g These unusual geodes from Morocco are like small caves lined with stalactites, botryoidal forms, and swirling agate patternsthough this one completely lacks the stalactitic growth forms common to this region. While commonly called red chalcedony, I find the color is more orange to red orange. Hematite causes this coloration, but later phases of growth (second

Locale: Atlas Mountains, Morocco

Approx dimensions: 4 x 4 x 3"

Approx weight: 588g

These unusual geodes from Morocco are like small caves lined with stalactites, botryoidal forms, and swirling agate patterns—though this one completely lacks the stalactitic growth forms common to this region. While commonly called red chalcedony, I find the color is more orange to red-orange. Hematite causes this coloration, but later phases of growth (“second generation”) don’t contain hematite inclusions and are white.

I call this one "the pie chart": one quarter matrix, one quarter swirling chalcedony, and 1/2 a beautiful geode. It's difficult to photograph to the back of the geode because it curves off into darkness. A snow-drift of white quartz flows out of the darkness, accompanied by fuzzy white snowballs of radial-growth quartz. Since chalcedony and quartz are closely related you often see them grow together. They have the same chemical composition (silica) but different crystal structure (cryptocrystalline vs. crystalline).

UV reactivity Near the geode entrance, a cluster of white blade-like growth is sprinkled with small double-terminated calcite crystals, which fluoresce and phosphoresce peachy-red under 365nm UV light. The chalcedony section fluoresces white.