There are many carbon patterns, but this one is tiny.
Source Designova
Some rectangles, a bit of dust and grunge, plus a hint of concrete.
Source Atle Mo
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Prismatic Floral Pattern 3 Variation 3 No Background
Source GDJ
Green Web Background, Seamless tile.
Source V. Hartikainen
Nice and simple crossed lines in dark gray tones.
Source Stefan Aleksić
You just can’t get enough of the fabric patterns, so here is one more for your collection.
Source Krisp Designs
So tiny, just 7 by 7 pixels – but still so sexy. Ah yes.
Source Dmitriy Prodchenko
From a drawing in 'Storia del Palazzo Vecchio in Firenze', Aurelio Gotti, 1889.
Source Firkin
Love the style on this one, very fresh. Diagonal diamond pattern. Get it?
Source INS
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Looks like an old wall. I guess that’s it then?
Source Viahorizon
Remixed from a drawing in 'A Girl in Ten Thousand', Elizabeth Meade, 1896.
Source Firkin
I’m starting to think I have a concrete wall fetish.
Source Atle Mo