A while back I was digging in my mine, near the bottom level of my map, and I found something odd-- clay! So, I cooked the four blocks I found and it gave me some bricks. Awesome!
I've never seen clay again. I consulted the Minecraft wiki and it stated that clay is more rare than diamonds but slightly easier to find since it often appears on the surface near sand.
I haven't done a ton of looking but so far I haven't found any clay on the surface. So, why would such a useful block be so rare? Is this a bug or by design?