What could the value of this Inesite be?

Hi does anyone know what the value of this Inesite could be. The person I got it from got it at a estate sale. The person said it was once displayed in a measeum. It is 3 and a half pounds. It looks like some how like brown something on the edges. Maybe to protect the Inesite sides? Thanks

Oh one more question. What would be the value if Inesite was transparent per carat. Or if you had 10 carats would the value per carat go up in price? Thanks. I did search the internet. I just could not find much info on this neat gem. Thanks