Sun Stones have been in Pokemon GO for over four years now. It is an evolution stone that is used to evolve a select group of Pokemon.
None of these Pokemon are exactly front-runners in the Pokemon GO contest of popularity, so it comes as no surprise that many players may not know which ones the Sun Stone can be used on.
Sun Stone in Pokemon GO
The Sun Stone is an item with very few uses, both in the mainline games and in Pokemon GO. Only five Pokemon require this stone to evolve, and four of these are currently in Pokemon GO: Gloom, Sunkern, Petilil and Cottonee.
Gloom requires 100 Oddish candies and a Sun Stone to evolve into Bellossom. The other three - Sunkern, Petilil and Cottonee - all need 50 of their individual candies along with a Sun Stone to evolve into Sunflora, Lilligant, and Whimsicott, respectively.
All four of these Pokemon families are Grass-types and are most commonly found in natural areas like grasslands, farmlands, parks, and woodlands.
The Sun Stone, like the other evolution items, can only be acquired after reaching level 10. Once at level 10 or above, spinning Pokestops or gyms gives players a small chance of getting an evolution stone, as does opening gifts from friends.
An evolution item is also a guaranteed reward for every seventh consecutive day of spinning a Photo Disc. This is from the entire pool of evolution items, so a Sun Stone is not guaranteed.
There is a single guaranteed Sun Stone in Pokemon GO. It is a reward for completing part two of a special research called "A Ripple in Time."