Sunplate Blocks can be found naturally on Floating Islands. They appear yellow as a single block, but if two blocks are put together, the material appears to be blue where the blocks meet. Making a 2x3 arrangement shows more blue material in the middle of the blocks, and the blue area continues to grow as the arrangement thickens. If you put 3x3 of this block into a square, the middle block will turn into a blue sunplate block.
Furniture can be made from Sunplate Blocks at a Sky Mill.
Floating Island Houses are made out of Sunplate Blocks.
