Remixed from a design seen on Pixabay. The basic tile can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Prismatic Groovy Concentric Background 5 No Black
Source GDJ
It looks like a polished stone surface to me. Download it for free, as always.
Source V. Hartikainen
Remixed from a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
This metal background pattern resembles a metal plate with rivets. Solid rivets on a metal plate.
Source V. Hartikainen
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Alternative colour scheme. 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
A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Alternative colour scheme.
Source Firkin
Alternative colour scheme for the original floral pattern.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
Prismatic Curved Diamond Pattern 4 No Background
Source GDJ
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A beautiful dark wood pattern, superbly tiled.
Source Omar Alvarado
Lovely pattern with some good-looking non-random noise lines.
Source Zucx
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Remixed from a drawing in 'Works. Popular edition', John Ruskin, 1886.
Source Firkin
You just can’t get enough of the fabric patterns, so here is one more for your collection.
Source Krisp Designs
Alternative colour scheme for the original floral pattern.
Source Firkin