Though this is an older bowl by the iron specialist, Kimura Morikazu*, first of Kyoto and later from Echizen, he specialized in a broad and diverse spectrum of yuteki-temmoku glazes including some later experimentation with yohen effects creating vivid iridescent surfaces. This partiuclar yuteki temmoku was a style he used for some time and though complex in its origins and technology it is rather simple in appearance which truly works in harmony with the simple form creating an evocative and even elegant object which in this case just happens to be one of my favorite things in the world, a well made and considered chawan.
"Harmony makes small things grow, lack of it makes great things decay." Gaius Sallustius Crispis
(*I should also mention if you do a search for Kimura Morikazu on the I, POTTER blog you will see several other pots in this style including another chawan and a guinomi.)