You can get Sand Grains two ways:
- Crafting it
- There is a 3/8 of sand falling and then breaking into three bunches of Sand Grains
In order to craft three bunches of Sand Grains, you need one piece of sand.
Obviously, the recipe is shapeless.
17w42a - Added Sand Grains. There is no way to obtain it without creative mode, and it does nothing
17w44c - Sand Grains are now craftable.
17w44d - There is a 1/3 chance of sand breaking into Sand Grains when falling
17w45a - Nerfed the chance of sand breaking into it to 1/8.
17w45e - Increased the chance of sand breaking into it to 3/8.
1.12 - Sand Grains are now used to craft Quick Sand Powder. Oddly, this wasn't a feature in any pre-releases, and was added in the finished release out of nowhere.