Cyan concrete blocks are used for decoration purposes.
To Make Cyan Concrete, you will need Sand Blocks, Gravel, Cactus, Lapis Lazuli and Blue Concrete Powder. Please follow the following steps to make Blue Concrete.
The next required item that you will need to find and get is gravel block. Take at least four of them using your iron shovel.
After that next required item you will have to find is cactus. You can find cactus blocks in desert biomes. Take at least one block of cactus.
After that you will have to find lapis lazuli gemstone. You need to find and get at least one lapis lazuli stone. Use your iron pickaxe to obtain it.
Cactus Green Dye
Now go towards the furnace and add one cactus block in the top box and coal in the lower box, you will get cactus green dye in the right-side box of the furnace. Add this dye into inventory.
Now move towards the crafting table to craft cyan dye. Add lapis lazuli gemstone and cactus green dye in adjacent cells of your choice in the 3*3 crafting grid. You will get cyan dyes in the right-side box of the crafting table. Bring these into your “ready to use” stock.
Cyan Concrete Powder
Now you will be able to craft Cyan concrete powder, because you have cyan dye, sand blocks and gravel blocks in your inventory. Head towards the crafting table and add these things into 3*3 crafting grid of the crafting table in the same way as shown in the image below.
Add 4 gravel blocks at the four corner cells, cyan dye in the center cell and 4 sand blocks in the remaining 4 cells of the crafting grid. You will get Cyan concrete powder in the right-side box of the crafting table. Add this item in your “ready to use” stock.
Now you can make a Cyan concrete block by placing cyan concrete powder in the water. After placing powder into water, you can obtain it by using any pickaxe.