There are many carbon patterns, but this one is tiny.
Source Designova
A seamless pattern formed from a square tile based on a jpg on Pixabay. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
Source Firkin
The file was named striped lens, but hey – Translucent Fibres works too.
Source Angelica
A light gray wall or floor (you decide) of concrete.
Source Atle Mo
Just the symbols of the signs of the zodiac distributed in a chequer board-like pattern
Source Firkin
A free seamless background texture of "timber wall" (colored in dark brown).
Source V. Hartikainen
A heavy hitter at 400x400px, but lovely still.
Source Breezi
A subtle shadowed checkered pattern. Increase the lightness for even more subtle sexiness.
Source Josh Green
Prismatic Curved Diamond Pattern 5 No Background
Source GDJ
A version without colours blended together to give a different look.
Source Firkin
Looks as if it's spray painted on the wall. You can be sure that this pattern will seamlessly fill your backgrounds on web pages.
Source V. Hartikainen
Zero CC tileable moss or lichen covered stone texture, edited from pixabay. CC0
Source Sojan Janso
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
A light brushed aluminum pattern for your pleasure.
Source Tim Ward
Not the most creative name, but it’s a good all-purpose light background.
Source Dmitry
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
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Brushed aluminum, in a bright gray version. Lovely 2X as well.
Source Andre Schouten
Prismatic Groovy Concentric Background 2
Source GDJ