Is a very rare mineral of the zeolite group with formula NaCa2Al5Si5O20 - 6H2O, an Hydrated sodium calcium aluminum silicate. The hardness is 5.5.
The radiating acicular structure makes it very difficult to cut and polish. The acicular crystal sometimes are hollows and may traps some polishing powder inside them.
It is rarely seen as facet gem. It may shows a partial cat’s eye effect. This gem comes from India. For collectors!
Weight: 5.44 ct.