There was an eruption of applause when The Cranberries' When You're Gone played as the service came to an end.
Her body has since been flown back to Ireland, ready for her to be laid to rest beside her dad Terry, who died from cancer aged 68, in their family plot at Caherally Cemetery outside of her home town of Ballybricken.
"The memory is indelibly written on my mind", he said.
"Now she is singing in the heavenly choir - hymns of petition for us", he said.
DeMarchi's younger brother Denny also played keyboards and guitar with the singer on her two solo records, and on tour. "She also knew that talents were given by almighty God to be used generously for the benefit of others".
"Her singing voice was unique, far-reaching and distinctly Irish".
The Mass began with a poignant recording of the Cranberries" star performing "Ave Maria' with Pavarotti, from a 1995 concert for the Children of Bosnia.
Later mourners heard her sing the moving Panis Angelicus.
A funeral mass was held for Dolores O'Riordan today at the Church of Saint Ailbe in Ballybricken, Limerick.
Other gifts brought to the altar included a poetry book and a picture of Our Lady of Dolours, originally owned by her great, great, great grandmother. Chief concelebrants will be Father James Walton PP, Ballybricken & Bohermore, Archbishop Kieran O'Reilly, Archbishop of Cashel & Emly and Archbishop Dermot Clifford, Archbishop Emeritus of Cashel & Emly.
The funeral was absent of the trappings normally associated with celebrity lifestyles and farewells.
Thousands pay their respects to Dolores O' Riordan.
Outside were a smattering of locals and a few fans, there to pay tribute but keen not to impose.
Meanwhile, fans have been paying tribute to O'Riordan since her sudden death on January 15.
"Those songs, Jesus, they go into your bloodstream", says HamsandwicH's Niamh Farrell who sang "Dreams" last night at the Hot Press and Tramline tribute to Dolores. We kept in touch and I'd be there for her. "We expected something maybe bigger, it was unusual for us".
"I'm just a fan".
Eileen O'Riordan (centre) following the funeral of her daughter.
As the cortege left the church grounds, Ms Bertoldo added: "She was an inspiration to us". Speaking personally - it was not unusual to receive from her a little word of support, encouragement, advice - always given quietly, in a whisper - "Mind yourself".