Solving this puzzle requires first identifying the Minecraft ores pictured. From top to bottom, they are gold, lapis lazuli, emerald, coal, diamond, iron, and redstone. If we then notice that each row has the same number of stone/ore blocks as the ore has letters in its name, we can fit each ore into the grid.
Reading the letters in the ore blocks, again from top to bottom, gives the answer, OPALINE.