Tin(II) sulfide Tin(II) sulfide Tin(II) sulfide is a chemical compound of tin and sulfur. The chemical formula is SnS. Its natural occurrence concerns herzenbergite (α-SnS), a rare mineral. At elevated temperatures above 905K, SnS undergoes a second order phase transition to β-SnS (space group: cmcm, No. 63). in recent years, it has become evident that a new polymorph of SnS exist based upon the cubic crystal system, π-SnS (space group: P23, No. 198). Tin(II) sulfide can be prepared by reacting tin with sulfur, or tin(II) chloride with hydrogen sulfide. Tin(II) sulfide is a dark brown or black solid, insoluble in water, but
Wedding anniversary for the 50th anniversary, and every fifth anniversary after that. In the United States, a couple can receive a greeting from the President for any wedding anniversary on or after the 50th. Roman Catholics may apply for a Papal blessing through their local diocese for wedding anniversaries of a special nature (25th, 50th, 60th, etc.). The names of some anniversaries provide guidance for appropriate or traditional gifts for the spouses to give each other; if there is a party these can be brought by the guests or influence the theme or decoration. These gifts vary in different countries, but some