UPDATE 1-Square CEO Dorsey says looking to build a bitcoin mining system - tweet

(Adds details from Twitter thread, background on Square's other bitcoin-related projects)

Oct 15 (Reuters) - Square Inc Chief Executive Officer Jack Dorsey said on Friday the fintech firm is looking to build a bitcoin mining system based on custom silicon and open source for individuals as well as businesses.

This would add to Square's existing bitcoin-focused projects including a business to build an open developer platform, as well as a hardware wallet for the cryptocurrency. (https://reut.rs/3plRcbh)

"If we do this, we'd follow our hardware wallet model: build in the open in collaboration with the community," Dorsey said in a tweet.

A team led by Square's hardware lead, Jesse Dorogusker, will investigate requisites for Square to take on the project to build a bitcoin mining system.

In his Twitter thread, Dorsey also said that silicon design or chip design is too concentrated into a few companies, leading to supply constraints.

Shares of Square were up about 1% in extended trading.

On Friday, bitcoin topped $60,000 for the first time in six months, since China's crackdown on bitcoin trading and mining, as hopes grew that U.S. regulators would allow a futures-based exchange-traded fund (ETF), a move likely to open the path to wider investment in digital assets. (Reporting by Chavi Mehta in Bengaluru; Editing by Shailesh Kuber)