I have known Mas Nakajima since the mid-1980s, when I joined the San Francisco Suiseki Kai. We have been close friends ever since. Mas is the president of the Japanese suiseki club, the San Francisco Suiseki Kai, currently in its 23rd year.
Mas got involved with suiseki via the Hirotsu family, who were friends of his family. That is the way he came to know the famous suiseki sensei Keiseki Hirotsu. Mas was born and raised in Japan. He came to San Francisco as a young man and he studied art at the San Francisco Art Institute. He started his own general contracting business and was able to retire about five years ago, allowing him to devote all his free time to the art he loves so much.
Mas is a contemporary thinker in the art. After all the years of having the suiseki exhibited at the San Francisco Suiseki Kai be judged by its sensei, Mas was able to convince the membership (after its sensei stepped down) to evaluate and award plaques to deserving suiseki by a committee of the whole. This was approved and put into practice in the '03 exhibition, to the acclaim of all the membership.
Mas' style in suiseki is a bold one, not shying away from large suiseki. He also doesn't hesitate to cut material when the art requires it.
Mas got totally involved with the pursuit of suiseki, finding its aesthetics in consonance with his artistic training. As you can see in the bottom of the page, Mas has developed a unique art style called, for a better term, "Rock Art". It's a visual and metaphorical extension of his suiseki appreciation, using large wood pieces as a continuation of his chosen symbols and metaphors. Arishige Matsuura has visited Mas was was most impressed both with his suiseki and his rock art. The November/December 2003 issue of Golden Statements magazine carried one of his photos on its cover. Mas has had his rock art exhibited at a downtown fine arts gallery in San Francisco several times throughout the years.