Carrageenan
Chondrus Crispus Extract
Red-algae thickener; appears on pore-clogging lists.
How solid is the pore-clogging number
Carrageenan rates 4 of 5 — frequently implicated in breakouts on acne-prone skin. The rating is graded disputed. Sources disagree. This figure circulates on clinic lists without a clear original citation, so treat it as a reason to patch test rather than a settled number.
It describes the raw ingredient in isolation. In a finished product, how much is present and where it sits in the list matter just as much. Check a whole label to see it in context.