The CajaGranada Foundation said in a statement late on Thursday that the missing piece - a small framed gouache titled "Still life with guitar" - was part of a larger shipment of artworks moved from Madrid to the Andalusian city for the exhibition "Still life. The eternity of the inert".

The foundation confirmed on Friday that the painting, owned by a private collector and measuring 13 x 10 centimetres (5 x 4 inches), was insured for an appraised value of 600,000 euros ($700,000).

The shipment was delivered to the CajaGranada cultural centre on the morning of October 3, a Friday.
The loss was not discovered until the following Monday, when the exhibit's curator and the foundation's head of exhibitions began unpacking the crates.

"As not all packages were properly numbered, it was not possible to carry out a thorough check without unpacking them," the foundation added.

The CajaGranada Foundation said it had reviewed the security footage from that weekend and confirmed "no incident occurred" during that time.

After discovering the painting was missing, the foundation filed a complaint with Spain's national police.

The organisation said it has made all its resources available to investigators and expressed confidence in the authorities' ability to resolve the case.
($1 = 0.8550 euros)

Reporting by Romolo Tosiani Editing by Peter Graff

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