Rembrandt

The Syndics

Rembrandt painted ‘The Syndics’ (1662) on a canvas with a pattern
The painting is in the collection of The Rijksmuseum
X-ray image RKD webpage of ‘The Syndics’
the pattern is called a herringbone twill

source: https://www.rijksmuseum.nl/nl/rijksstudio/kunstenaars/rembrandt-van-rijn/objecten#/SK-C-6,5

About the book on the table:

When I saw a close-up high quality picture from the book on the table I was convinced that it was a swatch book: the pages look like a woven textile . And it makes sense to me that The Syndics were together looking at a swatch book. The way one of the sample masters holds the page in his hand is how we ‘touch’ a piece of textile, between thumb and fingers.

But then I read that it has been overall accepted that the Syndics are looking at an account book .

One of the reasons for that idea is that Rembrandt made studies of the first two sample masters on the left on sheets of account-book paper and later in their account book. (Benjamin Binstock)

Account-book paper has a red line on the side…

Would Rembrandt not have painted these lines on the book in his painting if they were there ?