Nice idea, I liked the art. Especially the fact that the sand gets darker as you go deeper. The world is very large, I struggled a bit in finding the diamonds.
It would be nice if there is some way you can remember where you have been and where not, maybe a map that reveals the places you have visited.
As another comment already pointed out, I didn’t really get why you could extend the pipe. Floating over the diamonds seems to be enough. Another point of feedback: the gems sometimes went flying away (when vacuuming them but missing the collect hitbox I guess). Maybe they could slow/fall after some time?
Core gameplay is good and art is cute, a great entry for this jam :] well done!