What this suffix does
-hewn forms compound adjectives that describe material shaped by cutting, carving, or hewing — and by extension the roughness, authenticity, or handcrafted quality of a person's character. Rough-hewn, hand-hewn, raw-hewn, well-hewn, freshly-hewn — each compound describes the quality of the cutting and by extension the quality of what was produced. "Rough-hewn" is the most important figuratively: applied to a person it describes someone whose character has not been smoothed or refined by education, social polish, or cultural formation. These compounds belong to the literary tradition of describing character through craft metaphors.