Chromium Diopside/Tremolite, Graphite

Here's a curious one, what I believe may be chromium diopside, or perhaps a type of chromium rich tremolite (or perhaps a pseudo of both?) The specimen still needs proper identification to put a proper name to it. The milky white calcite matrix is also riddled, with many tiny flattened and rounded graphite crystals. The sample originates from Lac-Sainte-Marie, Quebec, an obscure yet notable locality within the Grenville Province, renowned for its abundance of pegmatites. During the Grenvillian orogeny, these rocks experienced intense deformation and high-grade metamorphism, resulting in a predominance of calcitic marbles in the region. Metasomatic reaction zones formed at the contacts between calcitic marbles and silicate rocks, generating higher-than-usual concentrations of crystal species, such as fluorapatite and diopside, making this specimen a good example from this geologically intriguing area.