Just finished brewing a nice simple extract pale ale, and learned a bummer of a lesson. I'm pretty upset that it happened. I should've known better because I work with metals often, but at the same time I would've never thought about it. I have used this equipment several times before without issue. I boil in a 5 gal kettle and stir with a smooth stainless spatula. I went about my normal brew, but was using a new yeast similar to us-05, and water to cool my wort as much as possible before pitching my yeast. In order to do that I submerged my kettle and aggressively stirred with a stainless spatula so that the whirlpool would cool it quickly. As a result, the spatula actually knicked and chipped the kettle. I didn't realize until I was cleaning the kettle on the sink and saw metal shavings in the sink and the dents in the kettle. The one saving grace is I poured the wort through a strainer into the fermenter. I just don't know if it caught the metal. Time to go stainless.