All Scarlet, Verdure, Crimson and Azure Stones in this Early Access Stage 1 - Gensokyo Nigh Festival.
Right at the beggining, all the way to the top. Keep holding Dash to get there.
Top of Gensokyo Outskirts - West of OldPath, same area where you fight Rumia. There's a Bell, hit it enough times and the Stone will come out.
Through a small hole at the top of Gensokyo Outskirts - Limestone Cave.
Top left of the Near Entrance - Ten Temple Gates.
Near Entrance - Forgotten Shrine.
Right above the rock blocking the tunnel at the Near Entrance - Tunnel Entrance.
Top of Near Entrance - Old Path Entrance.
Fake ground at the Near Entrance - Closed Road.
Hidden passage above the Shrine Approach Tunnel, at the Near Entrance.
At the Old Path - Water Fall. A hidden entrance from below.
At the Old Path - Tiny Plunge Basin, there's a Stone inside of a water mill. Use Bomb (Downwards, X) while Sparseness fully charge to frozen the water at the right time to be able to get it.
Hidden hole above Old Path - Waterfall Sound Rock Face
Old Path - Riverside Square. Kill this Yokai bunny.
At the Hakurei Shrine - Shrine Approach Tunnel Entrance, hidden hole from below.