Bitcoin tumbled 11% on Monday, its largest one-day drop in over a month, with losses of nearly 30% in the last week alone almost wiping out gains for the year-to-date.
The 101.38-carat pear shaped flawless diamond, dubbed The Key 10138, is one of just ten diamonds of more than 100 carats ever to come to auction, only two of which were pear-shaped.
The name of the colorless diamond - Key 10138 - is intended to reflect the integral role that keys occupy in the world of cryptocurrencies.
All crypto mines in the sparsely populated but coal- and hydropower-rich regions of Inner Mongolia and Qinghai were also ordered to shut down in recent months
BBVA said that during a gradual roll-out it had detected a "significant desire" among investors for crypto-assets or digital assets to diversify their portfolios despite their volatility and high risk.
BBVA said it was limiting this new cryptocurrency service to Switzerland because the country has clear regulation and widespread adoption of digital assets.
Tesla Inc Chief Executive Officer Elon Musk tweeted on Sunday that the electric carmarker will resume allowing bitcoin transactions when miners who verify transactions use more renewable energy.
The chief executives of Wells Fargo, Citigroup and Bank of America said at a congressional hearing in late May that they are approaching the cryptocurrency landscape with caution.