Calcite coated with Apophyllite

I spotted this piece in Bill Butkowskis (Mineral Cabinet) booth at the Macungie PA show in 2006. I have not seen one similar since. Very thin, platy calcite crystals completely coated in small, water clear, apophyllites, which also coated the thin shell matrix. Competition quality.

Locality: 2nd Sovietskiy Mine, Dal’Negorsk, Primorskiy Kray, Russia

Composition: calcium carbonate, potassium-calcium fluoride-silicate