A work awarded to the British artist Banksy will be auctioned in Zwolle on Thursday.
The artist never claimed the work, but experts do not doubt its authenticity.
What exactly is the difference between Certified and Uncertified Banksy's?
The work that is auctioned in Zwolle has the title
Bird with Grenade
It was allegedly applied by the anonymous street art artist Banksy in 2002 with a spray can on a plasterboard wall of the Libros Revolucion bookstore in Los Angeles.
Five years later, according to the offering auction house Hessink's, the now-carved spray can drawing was sold by Richard Duardo to Jamie Wood (son of Rolling Stones guitarist Ron Wood).
Duardo is the owner of Modern Multiples workshop and publishing house.
The amounts raised by Banksy's works during auctions vary enormously.
Millions can lie between the proceeds of a painting and a sawn-out work.
The work in Zwolle is estimated at between 150,000 and 200,000 euros.
This has several reasons.
It is largely determined by whether the work in question has been officially claimed by the artist.
Banksy has different ways of doing this.
The artist has been making work that is intended for sale for twenty years.
In 2000, when he was still relatively unknown, Banksy sometimes endorsed the authenticity of his work by means of a signature on a police report form.
He also sold a lot of work during solo exhibitions.
Banksy is taking action to combat counterfeits
Both signed and unsigned work changed hands frequently since then, until forgeries were spotted in the market and the artist took action.
In 2008 he founded Pest Control.
Via Pest Control, not only Banksy work is sold, but enthusiasts who have a Banksy in mind can also have it checked for authenticity.
In addition, Pest Control issues a certificate for Banksy's work created after 2008.
But paintings, stencils and other prints comprise only part of Banksy's work.
Since the early nineties he has concentrated largely on graffiti works in public spaces, often socially critical.
When the art world embraced Banksy, these works were automatically sought after.
Half walls, garage doors, power boxes and other objects have since been dismantled and put up for sale.
Since Banksy does not own the object to which he has applied the work in almost all cases, his role in the sales process is negligible.
In addition, in most cases it is impossible to prove that it was actually Banksy who used his spray can.
Unless he admits it himself, like at the end of 2018 when he was working on a garage wall in a small village in Wales.
On one side of that wall is a child in winter clothing, trying to catch the cut flakes from the air with his tongue.
On the other side of the wall, however, those snowflakes turn out to be ash particles from a fire.
Banksy posted a video of the work on his Instagram profile, and the garage owner sold the work for "a six-digit amount."
Letters must determine authenticity when Banksy is silent
When Banksy remains silent, sellers must provide other means to their customers that they are not offering counterfeits.
The potential buyer who
wants to purchase
De vogel met grenaat
in Zwolle has to make do with a 'certificate of authenticity' from previous owner Duardo.
This may not be convincing evidence for laymen, but those who investigate will find that Duardo has worked with Banksy in the past and also made prints for him.
The auction house also has a handwritten letter from radio DJ Michael Slate, who says he was there when Banksy put the bird on the wall of the bookshop.