Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Remixed from a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
Seamless Olive Green Web Background Image
Source V. Hartikainen
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin
A seamless textured paper for backgrounds. Colored in pale orange hues.
Source V. Hartikainen
Prismatic Groovy Concentric Background 5 No Black
Source GDJ
Colour version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
Love the style on this one, very fresh. Diagonal diamond pattern. Get it?
Source INS
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Tweed is back in style – you heard it here first. Also, the @2X version here is great!
Source Simon Leo
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
If you’re sick of the fancy 3D, grunge and noisy patterns, take a look at this flat 2D brick wall.
Source Listvetra
A nice one indeed, but I have a feeling we have it already? If you spot a copy, let me know on Twitter.
Source Graphiste
Formed from a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
A simple circle. That’s all it takes. This one is even transparent, for those who like that.
Source Saqib