There are many carbon patterns, but this one is tiny.
Source Designova
Remixed from a drawing in 'Paul's Sister', Frances Peard, 1889.
Source Firkin
A dark striped seamless pattern suitable for use as a background on websites.
Source V. Hartikainen
Prismatic Abstract Geometric Background 2 No Black
Source GDJ
A textured blue background pattern with vertical stripes.
Source V. Hartikainen
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
Paper pattern with small dust particles and 45-degree strokes.
Source Atle Mo
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A seamless pattern formed from cross 4. To get the original tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Seamless Prismatic Quadrilateral Line Art Pattern No Background
Source GDJ
Bright gray tones with a hint of some metal surface.
Source Hendrik Lammers
It was called Navy Blue, but I made it dark. You know, the way I like it.
Source Ethan Hamilton
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Remixed from a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892. The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
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
The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.
Source Nathan Spady
ZeroCC tileable beechwood wood texture, generated in Neo Texture Edit by me. CC0
Source Sojan Janso
A playful triangle pattern with different shades of gray.
Source Dimitrie Hoekstra
A beautiful dark wood pattern, superbly tiled.
Source Omar Alvarado
A seamless canvas texture for using as background on websites. Colored in pale tones of brown.
Source V. Hartikainen
Background formed from the iconic plastic construction bricks that gave me endless hours of fun when I was a lad.
Source Firkin