Hi, yes it is teak. But the panel in the door is a teak veneer over a thin plywood layup.
BEWARE that those commercial cleaning agents, like the 3-step products (clean, brighten, & oil) can "hurt" the teak, as the cleaner softens wherever the DARK spots are. Dark spots are actually dirt and where the fibers broke down.
What I did was to use a large floor/pad sander and tried to keep removing a consistent amount so as not to 'dish' any area. I sanded through the dirt, I did not use any chemical cleaners. I was not able to get it 100% (rid of all dimples or checks) but from 3 feet away, you can't tell.
I hit my teak with Sikkens Cetol Marine LIGHT for 2 coats, lightly buffed with a fine sctochbrite in-between. The door was so checked and had some porosity or lifiting of the veneer in places, that I removed it and then "painted" it with thinned self-leveling epoxy. Then the door and frame were coated with 3 or more coats of Interlux Gold Spar clear varnish/polyurethane (hey, that's how the ca nis marked) that has UV inhibitors.
Some just use oil on teak, but I don't like that it doesn't last. Besides, almost all of my teak/mahogany is fully encapsulated in epoxy before varnishing.
