| A skin blemish that forms when the sebum (oil) draining from a pore becomes blocked by a clump of dead skin cells. Its color results from the sebum’s pigment, which darkens when exposed to air. |
| A skin blemish that forms when the sebum (oil) draining from a pore becomes blocked by a clump of dead skin cells. Its color results from the sebum’s pigment, which darkens when exposed to air. |