By Lisa Pauline Mattackal and Bansari Mayur Kamdar (Reuters) – Bitcoin just isn’t anonymous enough for a growing cohort of crypto users who are seeking greater seclusion. A volatile class of crypto known as privacy coins, created with the primary aim of masking the identity of users and details of transactions, has quietly been gaining ground this month as maturing bitcoin inches towards mainstream finance. Monero and Zcash, among the most popular, have respectively gained 7.6% and 46% since March 1, according to CoinMarketCap data, even as bitcoin has lost about 5%. The pair has gained 4.7% a…