Gertrude Gaynor Jones, known as Gaynor, was found dead in her Aberaeron home following concerned welfare checks on 21 March.
Gaynor, 83, had lived in the small one-bedroom home at Dolheulog Cottages, off Panteg Lane which had no water or electricity with her 57-year-old daughter Valerie since 2012 following the death of her husband.
Valerie was found collapsed at the house by police, before a search of the property revealed the body of her mother.
DC Carys Sisto told the inquest that Gaynor’s body was so badly decomposed the cause of death could not be ascertained.
“She was found under a layer of rubbish and tarpaulins,” DC Sisto said.
“She was covered with grit and another tarpaulin, surrounded by bags of rubbish which contained human excrement and urine.”
Police were unable to enter the home initially due to the amount of rubbish filling each room and the garden.
The inquest heard that Valerie had given the impression over the years that her mother was still alive, and told police she could not remember Gaynor dying.
She told family members that she recalls a pile of books or a bookcase falling on her mother, but nothing of that nature was found by police.
The inquest heard that Valerie purchased four bags of rock salt in December 2015 and January 2016, with Ceredigion coroner Peter Brunton saying he gets “the inference that she used the salt to cover up or stop the decomposition” of her mother’s body.
The inquest heard that the last repeat prescription for Gaynor was picked up in December 2015, but that a definite date of death could not be recorded.
Valerie now lives in a mental care facility, the inquest was told, and the CPS said it was “not in the public interest” to prosecute Valerie with any offence.
The inquest heard that any charge would have been preventing lawful burial of a body, with no evidence or suggestion she was involved in her mother’s death.
Mr Brunton, recording a narrative verdict, said that on the balance of probabilities, Gaynor died of natural causes.
He estimated time of death to be between December 2015 when Gaynor was last thought to be alive, and the end of 2017.
He added there was “nothing sinister” about the death.