Kertschenite (vivianite) from the Ukraine – old find - large cabinet size

Kertschenite from the Ukraine.
Mindat.org states the following:
Kertschenite from a supposed hydrated phosphate of iron which is an alteration product of Vivianite. Later studies have shown an intergrowth of vivianite or Metavivianite with varying amounts of amorphous ferric iron phosphate (Santabarbaraite) and Bobierrite.
Comes with old label
11 cm x 6 cm x 4 cm
357 gram