Natrolite is actually quite rare in these zeolite pods, especially in such good specimens as this one. If a collector ever wanted to see an example of minerals forming in a vug, this would be a perfect candidate. The mineralizing fluids first deposited a thin layer of drusy quartz followed by drusy stilbite in the basaltic opening. It then got serious with an exquisite ball of lustrous, colorless, radiating, natrolite. The spray measures 3 cm across. I find it particularly mesmerizing, that the natrolite spray does not contact the sides of the vug. This is a beautiful specimen, with a story to tell. 8.5 x 7.2 x 7 cm