Go on eldritch island in CrystalIsles this is a little bit dangerous but you gonna have a lot of element shard.

Use the mining drill in the volcano on genesis on red crystals and then take the shards to a tek replicator to make loads of element

In the lunar biome, the mining drill only works on certain large nodes but gives high yield of shards on those. All the small rocks only give stone with the mining drill, so use Ankylo or Pick on the little ones.

Use an axe or dodicerous on Crystal isles, as they get more than with a pickaxe