Isaiah was born and raised at the San Felipe pueblo and learned jewelry-making from his father Raymond Twinhorse. Isaiah was born in 1976 and began making jewelry when he was fourteen years old. At eighteen years old, after graduating from the Santa Fe Indian School, he started selling under the portal of Santa Fe’s Palace of the Governors. Although inspired and taught by his father, Isaiah has created his own distinctive approach. He says his style “has come a long way” since his first simple pieces. His jewelry is fabricated using carving, saw work, and stone-on-stone inlay on some pieces. Geometric images predominate in his designs. He works in silver and occasionally uses exotic inlay materials such as White Angel turquoise, dinosaur bone and black coral. Isaiah has shown his jewelry at the Heard Museum and the Santa Fe Indian Market. One of his pieces is in the permanent collection of the Autry National Center Museum in Los Angeles.