The phrase "as coarse" is correct and usable in written English.
It can be used to compare the roughness or texture of something to another object or standard.
Example: "The fabric felt as coarse as sandpaper against my skin."
Alternatives: "as rough" or "as gritty".
This comically exaggerated figure, with bulging tennis-ball eyes, a tumescent nose and a plumed gladiator helmet, is as coarse as "Head of a Woman" is sleek.
Like Feste, Touchstone, in "As You Like It," is something of a professor of the life sciences, but his methods are as coarse as Feste's are kind.
They be as coarse as Ulik the Rock Troll and ravenous as the Fenris Wolf.
In contrast, the Australians were regarded by the social standards of the 19th century—as coarse, rowdy and uncultured.
She said: "The voice, as unique as you'll find by a female singer, is as coarse as ever.
gravel as coarse aggregate.
More generally, Manchester portrayed Johnson as coarse, crass and boorish.
The atmosphere struck Rosalind as coarse and schoolboyish.
The aji salsa can be as coarse or as smooth as you like.
Classified as coarse grazers, oryxes feed on grasses and energetically dig for water-storing roots and tubers.
Themes extracted from the training data are treated as coarse labels.
