Matlockite
... that the rare mineral Matlockite (PbFCl) is named after a town in Derbyshire?
... that the rare mineral <b id="mwCQI"><a href="./Matlockite" id="mwCQM" rel="mw:WikiLink" title="Matlockite">Matlockite</a></b> (<a href="./Matlockite" id="mwCQQ" rel="mw:WikiLink" title="Matlockite">PbFCl</a>) <i id="mwCQU">(pictured)</i> is named after a <a href="./Matlock,_Derbyshire" id="mwCQY" rel="mw:WikiLink" title="Matlock, Derbyshire">town in Derbyshire</a>?