A seamless gray background texture suitable for use on websites. To me, it has the look of stone. Feel free to modify it to meet your needs (by making it a bit lighter or darker, for example).
Source V. Hartikainen
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Almost like little fish shells, or dragon skin.
Source Graphiste
Prismatic Abstract Geometric Background 2
Source GDJ
Dark, crisp and subtle. Tiny black lines on top of some noise.
Source Wilmotte Bastien
Pattern formed from simple shapes. Black version.
Source Firkin
Used correctly, this could be nice. Used in a bad way, all hell will break loose.
Source Atle Mo
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Here's a repeatable texture that resembles a light green concrete wall or something similar.
Source V. Hartikainen
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
It’s a hole, in a pattern. On your website. Dig it!
Source Josh Green
Actually, there's no clouds in it, but I think it looks quite nice.
Source V. Hartikainen
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Derived from a corner decoration itself found as a jpg on Pixabay.
Source Firkin
There are many carbon patterns, but this one is tiny.
Source Designova
Super subtle indeed, a medium gray pattern with tiny dots in a grid.
Source Designova
Colorful Floral Background 3 No Black
Source GDJ
Embossed lines and squares with subtle highlights.
Source Alex Parker
It has waves, so make sure you don’t get sea sickness.
Source CoolPatterns
Derived from an image that was uploaded to Pixabay by pugmom40
Source Firkin
A bit like some carbon, or knitted netting if you will.
Source Anna Litvinuk
No, not the band but the pattern. Simple squares in gray tones, of course.
Source Atle Mo
The file was named striped lens, but hey – Translucent Fibres works too.
Source Angelica