Raoul Pal suggests that capital rotation may be driving the surge in Zcash.

Zcash is a decentralized cryptocurrency focused on privacy and anonymity. It uses the zk-SNARK zero-knowledge proof technology that allows nodes on the network to verify transactions without revealing any sensitive information about those transactions.Contrary to a common misunderstanding, the majority of cryptocurrencies on the market, including Bitcoin (BTC), are not anonymous, but rather pseudonymous; while they do not explicitly reveal the identities of their users, each user has their own public address or addresses which can be traced back to them via the methods of data science and blockchain forensics.Zcash transactions, on the other hand, still have to be relayed via a public blockchain, but unlike pseudonymous cryptocurrencies, ZEC transactions by default do not reveal the sending and receiving addresses or the amount being sent. There is an option, however, to reveal this data for the purposes of auditing or regulatory compliance.Zcash was first released on October 28, 2016, and it was originally based on Bitcoin’s codebase.