Prismarine Tools/Armor

One of my favorite Minecraft Ideas that I have is the concept of Prismarine Armor and Tools. First, I must state my knowledge of the idea that not every material requires a material, like Emeralds. Emeralds are used as currency, and do not need to be used as a material to craft tools or weapons. I do realize that this could be argued for Prismarine as well. But first, listen to my idea.

Prismarine could have an ore found on ocean floors. The armor crafted by Prismarine could be somewhat of a boosted turtle helmet. The Helmet would give the player five minutes of water breathing, and the leggings would give depth strider. Prismarine Weapons would remove all hindering of mining  underwater. 

Finally, other weapons and tools would need to be nerfed underwater. Swords would have a large cooldown when underwater. When underwater with armor, the player would be prevented from swimming and would walk slowly on the bottom. Of course, Prismarine Armor and Weapons would not have any of these debuffs.