how to find out is the Joan Miro’s painting real

Please help me if u have experience or are in this business , my families have antique art collection as Joan Miro, Ivazovsky, Shishkin, Zverev and want we want to sell few of the their artworks, I need help
how to proof that it is original and if u dont have any documentation proofs u bought and most of them was a gift ,how to proof ownership. if you have any information which art dealers works on antique artworks in LA?
thank you

 

You generally do not have to prove ownership to sell - most auction houses will have you sign paperwork stating you are the sole owner of the work you are selling. It helps to have provenance but many do not. In my humble opinion, I would not sell to an art dealer but to a reputable auction house that handles that artist. Their specialists will be able to tell you if your work is correct. I have spent the past 8 years in auction houses and before that was an accredited appraiser with the ISA. I did not handle a lot of the artwork because that was not my specialty but many times our specialists would reach out to individuals or authors working on catalogue raisonne for specific artist to obtain info about a work (whether it was done by that artist's hand). We do not authenticate as a rule but can agree when something appears to be correct or not. You best bet might be to seek out an accredited appraiser with the ASA or ISA in your area to get started. They will be able to provide you with fair market valuation if the work appears to be correct. They should be able to give you an opinion on the best marketplace for that artist as well. https://www.appraisers.org/Home https://www.isa-appraisers.org/