Decades ago, experts announced that a painting by Rembrandt known as Head of a Bearded Man had not actually been painted by Rembrandt at all.

It sat in the basement of the Ashmolean Museum in Oxford for years.

But over the weekend, a group called the Rembrandt Research Project said they’d looked again, and actually it probably was a genuine Rembrandt.

via GIPHY

The authenticity of Rembrandt paintings has been such an issue over the years that there have actually been museum exhibits of these non-official paintings.

Sadly, these shows were not called “I Can’t Believe It’s Not Rembrandt!”

So why is it so hard to sort out which are real and which aren’t?

For one thing, Rembrandt lived and worked in the 1600s, and there isn’t always a long paper trail for these works.

Also, Rembrandt taught dozens of painters.

He encouraged them to paint in his style and, sometimes, to make copies of his works.

Sometimes he helped them finish pieces, or corrected some of their brush strokes.

There’s a lot of detective work that goes into determining whether a painting is an actual Rembrandt or not.

They compare the relatively small number of works he signed to the many unsigned pieces to see what they have in common.

There’s also all kinds of technical and scientific analysis.

In the latest case, it took a dendrochronologist, someone who studies the rings of trees to determine their age, to verify that the wood for the painting came from the same tree as another verified Rembrandt work.

And this study continues, which means there could be more paintings coming out of museum storage in the years to come.

via GIPHY

Here’s a fun site for you to check out today: an interactive online map of continental drift!

You enter a town or city and see where that place was on the globe hundreds of millions of years ago, and how it got to where it is today.

The Rembrandt Research Project: Past, Present, Future 

A Supposedly Fake Rembrandt Might Just Be Real (Vanity Fair)

Map Lets You See How Your Hometown has Moved Across 750 Million Years of Continental Drift (Good News Network)