You can use a turtle to get flint too!
Put a stack of gravel in the first slot. He will place it, and break it until all the gravel has turned into flint. One stack takes about 5 minutes and no damage to your shovel.
while m >= 2 do
Additionally, Rockwool is essentially wool that doesn't burn. It has the same properties (hardness too) as stone, but you get the colors. So you can build things out of wool and not worry about it burning down.