This is the 6354th most frequent Japanese word.
ザラザラ
Rough, gritty, or coarse.
'ザラザラ' here describes the rough texture of the floor, emphasizing the presence of particles or unevenness making it uncomfortable.
床がザラザラしているので掃除しました。
The floor felt rough, so I cleaned it.
In this context, 'ザラザラ' illustrates the coarse and uneven surface of the river stones.
川の石はザラザラしており、歩くのが難しいです。
The river stones are coarse and rough, making it difficult to walk on them.
Here, 'ザラザラ' conveys the textured quality of the paper's surface which is ideal for certain artistic purposes.