Q:

Where are all the purple eridium totems?

As mentioned in this question, I've been finding eridium totems while playing through Sir Hammerlock's Big Game Hunt. By now I believe we've found 4 totems and dumped nearly 100 eridium into them, but there seem to be more to go.
Where are all the eridium totems located? Map(s) are ideal.

A:

This link contains maps to all of the Eridium Totems: 
http://orcz.com/Borderlands_2:_Dexiduous_Eridium_Totem_Furnace
There's four of them, all in Hunter's Grotto. Image from http://orcz.com reproduced here:

