I was just perusing the beautiful rocket mass heaterthread and thought a new thread should be dedicated to beautiful earthen floors. If I'm missing an obvious thread already created, feel free to point me in the right direction. So I'll start with a photo or two of my own floor in my cob house and hopefully get the ball rolling with some amazing looking floors. If you want to see more photos of my floor or house check my blog http://montanacobcottage.blogspot.com/
I'm building a tiny house Earthship and am planning the floor. What materials have you guys made your floors with? I'm thinking I have to do a layer of cement because here, anything, and I mean anything that is out in the ground will either have a root up in it, but especially some insect burrowing through it. I'm thinking of trying to put a layer I've cob over this to make it more human friendly.
My wife and I laid this floor in our entryway. When we cleared some pasture land in back of our house, I found a lot of slate slabs out in the field. It took some wrangling to get those huge blocks of slate close to the house where we used chisel and hammer to split them into thinner pieces. This slate was laid over radiant floor heat and if I ever figure out a faster way to split slate other than a hammer and a chisel we might do the entire great room. We have a shoe-less home and the warmth radiating from that slate on bare feet is wonderful.
Alex-- My recipe used for the floor was silica sand (70 grit), red art clay, wheat paste, horse manure, borax. I also used an aliz painted on top to get a smoother finish which had the same materials, but sifted very fine straw instead of horse manure. After drying I finished it with five applications of linseed oil. After the linseed oil I topped with a coat of pure tung oil and a coat of Heritage Natural Finishes floor liquid wax. I highly recommend going to http://www.heritagenaturalfinishes.com/ and checking out their products. If you have the cash to spend I would recommend getting all of your oil from them as they are really great and much better than the smelly boiled linseed oil I stooped to for the cost (also drop Cob Cottage Company's name and you might get a discount price).
If you are interested in floor I really recommend "Earthen Floors: A Modern Approach to an Ancient Practice" by Sukita Crimmel who helps run Claylin Earthen Floors out of Oregon. They even ship pre-made earthen floor mix right to your doorstep!
That slate floor looks great, I used some flagstone in my bathroom. Instead of building the floor around them which I thought might be a pain I just squished them into the earthen floor mix while it was wet and made sure they were level.