Yofortierite,  (Mn,Mg)5Si8O20(OH)2•8-9(H2O), Demix-Varennes quarry, Saint-Amable sill, Varennes &amp; St-Amable, Lajemmerais RCM, Montérégie, Québec, Canada. Tufts &lt; 2 mm. MOB coll. “Black” yofortierite. From a small specimen with the yofortierite spanning &gt; 1½ cm and looking nearly black in part.