RIO DE JANEIRO, March 12 (Reuters) - A board member from Brazilian miner Vale who resigned on Monday said his decision to do so came after the succession process of the firm was conducted in a "manipulated manner", according to his resignation letter seen by Reuters on Tuesday.

In the letter to Vale's chair, Jose Luciano Duarte Penido said the process of choosing a new CEO had "evident and nefarious political influence". (Reporting by Marta Nogueira; Writing by Peter Frontini; Editing by Steven Grattan)