Composition: Sodium calcium aluminosilicate hydroxide
Nomenclature: Named after the Greek word "mesos" which means "middle" because of its chemical position between natrolite and scolecite.
Industrial Uses: Chemical filters.
Additional Notes: A member of the Zeolite group of minerals.
Faroe Islands : Scott 242 : 6.50 krone : 9 Jun 1992
French Southern and Antarctic Territories : Scott 146 : 5.10 francs : 1 Jan 1989