Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
Floral patterns might not be the hottest thing right now, but you never know when you need it!
Source Lauren
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
Actually remixed from a pattern on Pixabay. But then noticed a very similar one on Openclipart.org uploaded by btj51q2.
Source Firkin
Prismatic Groovy Concentric Background 2 No Black
Source GDJ
Formed by heavily distorting part of a an image of a fish uploaded to Pixabay by GLady
Source Firkin
A pattern formed from a photograph of a 16th century ceramic tile.
Source Firkin
An interesting dark spotted pattern at an angle.
Source Hendrik Lammers
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Formed by heavily distorting part of a an image of a fish uploaded to Pixabay by GLady
Source Firkin
This background has abstract texture with some similarities to wood.
Source V. Hartikainen
Luxury pattern, looking like it came right out of Paris.
Source Daniel Beaton
A seamless pattern drawn originally in Paint.net by distorting a slice of background pattern 116 and copying the resulting triangle numerous times.
Source Firkin
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Remixed from a PNG that was uploaded to Pixabay by k_jprather
Source Firkin
The tile this is formed from can be retrieved in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Got some felt in my mailbox today, so I scanned it for you to use.
Source Atle Mo
Remixed from a design seen on Pixabay. The basic tile can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Derived from an image that was uploaded to Pixabay by Darkmoon1968
Source Firkin
Prismatic Geometric Pattern Variation 2 With Background
Source GDJ