You can give your shards to people in various houses around Sinnoh. They all have a sign outside saying 'Shards wanted!' To get you started, there is one on the beach east of Pastoria.
Chat with our AI personalities
yellow shard and red shard and green shard
Blue Shard- Route 124; Wild Pokemon. Green Shard- Route 126; Wild Relicanth. Red Shard- Route 124; Wild Pokemon. Yellow Shard- Route 126; Wild Pokemon.
Red Shard Blue Shard Yellow Shard Green Shard Violet City and Fuchsia City
You can get them underground.
great marsh look for it or talk to the ace trainer who willgive you a random shard or go to fuego ironworks and ask mr fuego to give you one of each shard for a star piece