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  • A striking vivianite specimen featuring dramatic sprays of nearly black crystals with metallic luster contrasting against rusty iron-rich matrix. The 15 cm piece from the Crimean locality displays exceptional preservation, scattered calcite spheres, and represents an unusually large example of this distinctive phosphate species.
  • A striking vivianite specimen featuring dramatic sprays of nearly black crystals with metallic luster contrasting against rusty iron-rich matrix. The 15 cm piece from the Crimean locality displays exceptional preservation, scattered calcite spheres, and represents an unusually large example of this distinctive phosphate species.
  • A striking vivianite specimen featuring dramatic sprays of nearly black crystals with metallic luster contrasting against rusty iron-rich matrix. The 15 cm piece from the Crimean locality displays exceptional preservation, scattered calcite spheres, and represents an unusually large example of this distinctive phosphate species.
  • A striking vivianite specimen featuring dramatic sprays of nearly black crystals with metallic luster contrasting against rusty iron-rich matrix. The 15 cm piece from the Crimean locality displays exceptional preservation, scattered calcite spheres, and represents an unusually large example of this distinctive phosphate species.

VIVIANITE WITH CALCITE

Kerch Peninsula, Crimea, Ukraine
18.9 x 8.7 x 8 cm
$1,500.00
$1,500.00
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ABOUT THE SPECIMEN

Abundant sharp and lustrous sprays of vivianite atop a large plate of matrix, accompanied by a few spherical crystals of contrasting light calcite. As is typical with Crimean vivianite, the color is so deep it's almost black, and the luster is near metallic. This is far, far larger than almost any other piece you'll find on the market from this locality. Even if most of that is host rock, the display is also much more dramatic than one would usually see from here! Considering the number of sprays and their positioning at the base, this one is really in remarkable condition.

 

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MORE INFO

The Kerch iron-ore deposits formed in middle Pliocene sediments of an ancient shallow sea, producing ooidal ironstones in which phosphorus concentrated through early diagenesis in reduced brackish-water conditions - the mechanism Sokol et al. documented through detailed REE geochemistry of the Kamysh-Burun deposit. Vivianite precipitated as a secondary iron phosphate within this diagenetic environment, with two distinct occurrences: crystal druses grown in open vugs within the oolitic ironstone, and cavity-fill replacements within fossilized bivalve and gastropod shells, the latter producing specimens that are simultaneously mineral, fossil, and pseudomorph. Freshly extracted crystals are dark green, shifting to the characteristic deep indigo-blue as ferrous iron oxidizes on exposure to air; continued oxidation drives further transformation into metavivianite and ultimately santabarbaraite, meaning specimen condition is perpetually in slow decline. The Kerch basin is also the type locality for both anapaite and mitridatite, and vivianite-in-fossil-shell pieces frequently occur alongside anapaite and barite as a phosphate assemblage with no close parallel elsewhere. Political circumstances following 2014 have severely complicated access, and specific phosphate-bearing pockets within the deposit appear largely exhausted; fine fossil-shell vivianites in particular have become genuinely difficult to source.