Hi, There's a good chance that the knobs are steel and were originally plated (brass or copper finish). With the plating worn off, the dark finish you are seeing is dirt and rust. If you soak the knobs in lacquer thinner and scrub with a wire brush or coarse steel wool, you may reveal the steel and remnants of the plating. Test with a magnet to determine ferrous metal content. Lots of very cool knobs and plates are sold on ebay. Search for antique hardware, then refine by going under doors/door hardware section. The only thing to watch for is that the spindle/keyhole spacing is the same as your old locks. Occasionally, the spindle sizes vary, but mostly they are around 9/32 for interior doors. Casey

Hmm, good info but I am still undecided! The door will be a new SLAB, 1.75" douglas fir. It's going into an existing frame, so we thought to order it slab-only (undrilled/unmortised) so we could make sure the lock parts fit together right with the frame. Sounds like it's definitely more difficult for the average DIY-er to install a mortise set, which we'd thought. I think we're leaning towards the tubular, for ease of install and cost, but this is a fairly high-end reno and I wasn't sure it would seem too cheap to use tubular (Or if anyon would ever notice!)

How is this working? How did you attach this securely to your vinyl gate? What type of exit mechanism do you have? Panic bar?

I’ve been using the Kwikset Kevo lock for 4 years now, I’m actually on the second generation now that I got a new front door. It is a great system overall, but there can be issues. If your WiFi craps out it can be a pain to deal with, and sometimes you have to turn on and off the app. So it has its issues. But I like that I can send keys to anyone I want (and set timers on those keys), I like that I can monitor when and who goes in and out. I also like not having to actually use a key, but like I said it’s still sometimes a pain that i have to dig my phone out of my purse anyway (usually when I have a million bags of groceries in my hands) LOL.