Diamonds are Alexander's best friend?

Comparison:

[From “My Shot“] I’m a diamond in the rough, a shining piece of coal.

When Lin-Manuel Miranda wrote these words for “Hamilton“ in Hamilton he knew a vintage metaphor could carry the weight of the moment. Expressing youth, inexperience, and potential, all pointing toward eventual potent achievement, Miranda realised that this lyric would carry the day--even into the room where it happens.

Context:

[This comparison comes from the Broadway, and International, Hit: Hamilton.]

Citation:

Miranda, Lin-Manuel. Hamilton. 2015.

(Coal/Diamond image public domain via USGS; thanks to wikimedia for access)