Type Refining
Cost $500
Requires Efficiency
Leads To Extraction Tuning
Hitpoints 3
Effect +1 Extraction Rate

The Collector is a Refining building in Revenge of the Titans. Collectors increase the speed at which Refineries collect crystals (+$1/3sec each, for each Refinery in range).

However, it's not very likely for you to make a profit off placing Collectors. Two additionnal Refineries are usually a more sensible option if you don't have space issues.

As a general rule, the entire Refining research tree is optional. You can make enough money without them and the technology is not very effective.