Dried sea foam
Dehydration --skin, lips, etc
Over gelled hair
Pie crust/Pizza crust
Custards, baked gratin
Sugar/salt rim on drink glass
Flaky, crispy, brittle, well baked, scabby
Describing texture in a story creates intimacy between reader and character, and can even cause an emotional trigger for both. To anchor the reader in the scene, make sure comparisons and contrasts are clear and relatable, and within the scope of the narrator's life knowledge and experience.
A weak example:
After two days wandering lost in the Mojave desert, Oman's face was crustier than a freezer burned steak.
What's wrong with this example?
Desert...freezer burn? There's a lot better comparisons that don't mess with the hot/cold thing going on.
A stronger example:
After two days wandering lost in the Mojave desert, Oman's face was crustier than a charred loaf of bread.
Why does this example work?
This one provides a good crusty comparison and has the added bonus of a visual tying sunburn to burned bread.