Stephen Earl said a post-mortem examination has taken place, as he opened the inquest at Westminster Coroner's Court this morning.
But on the day she was scheduled to record, O'Riordan was found dead in her London hotel room with officials so far have labeled the case as "unsuspicious".
She had been staying at the Hilton on Park Lane.
"The London Ambulance Service was contacted and verified her death at the scene".
Police say they don't consider the death suspicious, meaning they have found no sign of foul play.
The Irish musician, originally from Limerick, led the band to global success in the 90s with singles including Linger and Zombie.
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After a breakout season in 2017 the Englishman continues to impress and could hardly have played better under the circumstances. Every hole it seems like I've got good memories of, so it really is drawing from some of those past experiences.
The parish priest from her home town has confirmed her funeral will take place in Co Limerick. The track is dedicated to Dolores and all profits from the track will go to Dolores' three children.
The band set up a session with O'Riordan in London not sure if she would add a lead or backup vocals to their grinding version, and in the wake of her death they still don't know what her plans were.
Earlier this week, O'Riordan's bandmates paid tribute to the Irish singer on Twitter, writing: "We are devastated on the passing of our friend Dolores".
The singer was due to re-record the song with the band on the day she passed, but they have made a decision to instead release the song in her memory, with the proceeds going to Dolores' three children.
"It's such a powerful song and the themes are still so relevant, we wanted to release it in her memory", he continues.
However, in May - shortly into the European tour - the group had to cancel the remainder of the European dates as a result of O'Riordan's health issues.