Prismarine Glass

Prismarine glass is a variant of glass.

Natural Generation
Several structures in Byatis have prismarine glass.

From Block Loot
Prismarine glass can be mined with any tool enchanted with Silk Touch

Smelting
If prismarine sand is smelted in a furnace, it turns into prismarine glass.

Info
Just like glass, prismarine glass blocks adjacent to other prismarine glass blocks are invisible when viewed through prismarine glass.

Though mobs can't normally spawn on top, zombie reinforcements are able to.

Crafting
2 prismarine glass, 1 lapis, and 1 bookshelf make 1 enchanted bookshelf. Regular glass can also be used, but not stained glass.

Lore
Similar to glass being made from sand, prismarine glass is a superheated, processed version of prismarine sand. Its hue and patterns shift slowly (GIFs don't support translucency, so the picture here isn't animated), which is often found satisfying to watch. Due to the large grain structure of prismarine sand, it would be very difficult to turn the glass into panes (may add that later, but those currently aren't in the mod, don't try it).