Law of thirds, golden ratio

This is a piece that I created lately for my friend Nathan. He had asked me for an abstract piece several months ago. I have been looking around for just the perfect flat object to work on. I finally found an old chalkboard in my own house. What a find. We purchased an old house last June that we adore and there are neat things lurking in nooks and crannies. In addition to it being a great old object, it also came complete with two holes ready to hang on a wall. I had been thinking of one of my favorite tools or themes used in art: the golden ratio. I wanted to use that in my painting because I have always found that concept to be very beautiful and also peaceful. The idea that everything can be broken down to it's base level and organized, very appealing. Here is what I came up with. It was fantastically fun to work on and I am full of new ideas now that I want to try to execute.