Not hard at all to obtain.
We all have our personal objectives in wet tumbling. Mine is brass having a "jewelry-like" appearance. Like these recent batches, for examples of typical results:
Now, we all know that the gun doesn't care what the brass looks like as long as it cycles well. But that's not the complete objective of my hobby. I get personal satisfaction from achieving this level of brilliance. It's achieving my personal expectations that makes this whole exercise one I want to repeat over and over. Each weekend, hopefully.
Obtaining clean brass, but rather dull looking brass, requires only soap, water and a bucket. Ask me how I know. But that's hardly what I'm after.
All the Best, Guys!
Bayou