(Corrects to say 15-month, not 18-month highs)
LONDON, June 24 (Reuters) - Bitcoin pulled back from 15-month highs on Monday after jumping more than 10% over the weekend, with analysts ascribing the spike to growing optimism over the adoption of cryptocurrencies after Facebook unveiled its Libra digital coin.
The biggest cryptocurrency touched $11,247.63 on the Bitstamp exchange on Sunday, its highest since March last year. On Monday morning it had pulled back from those highs, and was last down 0.5% at $10,786.
Mati Greenspan, an analyst at eToro, said the gains underscored optimism among retail investors over moves by major companies to adopt cryptocurrencies.
"Traders are speculating on future involvement of large players like Facebook," he said. "They believe that Libra will create mass awareness of cryptocurrencies and act as a gateway to adoption."
Facebook announced ambitious plans last week to launch a new global cryptocurrency called Libra.
Reporting by Tom Wilson Editing by Tommy Wilkes