This metal background pattern resembles a metal plate with rivets. Solid rivets on a metal plate.
Source V. Hartikainen
Prismatic Geometric Pattern Background 2
Source GDJ
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
This pack of filters can help you adding a blocky overlay to objects. May come handy at drawing blocks of stone.
Source Lazur URH
Don’t look at this one too long if you’re high on something.
Source Luuk van Baars
Prismatic Groovy Concentric Background 2
Source GDJ
A free grid paper background pattern for using on web sites.
Source V. Hartikainen
Super subtle indeed, a medium gray pattern with tiny dots in a grid.
Source Designova
You just can’t get enough of the fabric patterns, so here is one more for your collection.
Source Krisp Designs
A green background pattern with warped vertical stripes and a grunge look.
Source V. Hartikainen
Prismatic Triangular Seamless Pattern III With Background
Source GDJ
A seamless pattern formed from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
More in the paper realm, this time with fibers.
Source Jorge Fuentes
Remixed from a drawing in 'Canadian forest industries July-December', 1915
Source Firkin
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A large pattern with funky shapes and form. An original. Sort of origami-ish.
Source Luuk van Baars
Sharp pixel pattern looking like some sort of fabric.
Source Dmitry
This beige background pattern resembles a concrete wall with engravings or something similar to it.
Source V. Hartikainen
Carbon fiber is never out of fashion, so here is one more style for you.
Source Alfred Lee
Remixed from a drawing in 'Paul's Sister', Frances Peard, 1889.
Source Firkin
Remixed from an image on Pixabay uploaded by Prawny
Source Firkin