Not every ore spawns at diamond level...
I haven't seen gravel aluminum ore, either. Maybe I'm just unlucky. Actually, I haven't seen any aluminum at all. Wonder how it ended up in my ME system.
Yes, oreberries are awesome. I've found enough of them to make a wall of aluminium-oreberries. Got a lot of stacks of the berries, haven't been bothered to make something of them. But yes, they are a great source. They're mostly found deep down though, near lava lakes.
Just annoying really as I'd like to use tinkers to craft some tools but without Aluminium its not possible.
Yes, the gravel-ore is basically there if you don't want to risk going underground. Just spelunk enough on the surface and you'll get enough to start, most likely.this is just speculation, but I wonder if TC ore generation mechanics dont follow conventional rules. the gravel nodes mimic oreberries in placement and both only seem to spawn in open areas like a flower or mushroom would, not as a replacer for stone or gravel. if this is the case, then quarrying for it would be very unproductive because it is likely only found in open caves or on the surface. a very bass-ackwards way of implementing ore generation but meh