You can either your invedit a mod or you could use an in game mod called too many items
you NEED a Cobble stone pickaxe.
Re you sure you are using an iron pickaxe? Diamond cant be mined without an iron or diamond pickaxe Otherwise, it could be bug
You will need the 0.3.3 update.
bedrock in minecraft and you cant even mine it with a diamond pickaxe
Diamond is 10th layer and below
Ether a iron pick or an diamond.
The item ID for a diamond pick in Minecraft is 278. I have linked you below in the related links of a full list of all the ID's in Minecraft.
There are no diamond picks in Minecraft PE.
There is a Minecraft song called 'In Search of Diamonds'.
To get diamond, you need a pickaxe of iron, gold or diamond.
You can make a diamond sword in Minecraft by placing two diamonds above a stick in the crafting table.
Diamond Armor, Diamond Tools, other stuff like Jukeboxes. The rarest material of all.. diamonds. You find some, you should be happy Diamond is the highest tier in UNMODDED minecraft. See DIAMOND.