Xbox One Cleansing corruption/crimson/hallow

[Dracaen]

Something that has always frustrated me is that I've never been able to completely able to purify a world, there will always be 1% left and I have no idea how I should even be able to find those few last spots.
Is there any item or trick to find these small spots? I wish there was some kind of corruption/hallow gieger counter that pointed me in the direction of the infected area, or just some kind of purity nuke.

 

[Mille Marteaux]

The most common and effective method (is rather time consuming, but) involves multiple hellevators dug at regular distances through the entire world, then going down each and every one of them firing the Clentaminator to hit every last spot of it. From there you find your ideal farming locations, quarantine them, and make your own localized evil/hallow biomes.

 

[Dracaen]

That is a good idea but I'm trying to look for something that wont leave holes on the surface or anything, and I just kind of want to see what the dryad says for myself, I also just think it would just be neat to have too.
It's also on the special bee seed, on journey mode in a small world, so I have infinite materials to try and cleanse but there is this one tiny molecule of crimson that somehow I didnt hit.
I chose journey mode as well as this world type to make it easy to remove the crimson.