Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
This one needs to be used in small areas; you can see it repeat.
Source Luca
Super subtle indeed, a medium gray pattern with tiny dots in a grid.
Source Designova
Your eyes can trip a bit from looking at this – use it wisely.
Source Michal Chovanec
Pattern formed from simple shapes. Black version.
Source Firkin
This pack of filters can help you adding a blocky overlay to objects. May come handy at drawing blocks of stone.
Source Lazur URH
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin
ZeroCC tileable stone texture, edited from pixabay. CC0
Source Sojan Janso
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Number 5 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Remixed from a drawing in 'Works. Popular edition', John Ruskin, 1886.
Source Firkin
Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Seamless Prismatic Pythagorean Line Art Pattern No Background. A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ
Tiny little fibers making a soft and sweet look.
Source Badhon Ebrahim
I have no idea how to describe this one, but it’s light and delicate.
Source JBasoo
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
A repeating background for websites with a texture of black groove stripes.
Source V. Hartikainen
Turn your site into a dragon with this great scale pattern.
Source Alex Parker
High detail stone wall with minor cracks and specks.
Source Projecteightyfive
A colourful background drawn originally in paint.net and vectorised in Vector Magic.
Source Firkin