The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
New paper pattern with a slightly organic feel to it, using some thin threads.
Source Atle Mo
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Zero CC tillable hard cover red book with X shape marks. Scanned and made by me.
Source Sojan Janso
Drawn in Paint.net using the kaleidoscope plug-in and vectorised.
Source Firkin
It looks like a polished stone surface to me. Download it for free, as always.
Source V. Hartikainen
This is the remix of "Strawberry Pattern Background" uploaded by "GDJ". Thanks. I realigned strawberries so as to get seamless and changed the BG color.
Source Yamachem
Here's a seamless brown cork board background texture. Feel free to download or reshare if you like.
Source V. Hartikainen
Remixed from an image on Pixabay, the original having been uploaded by darkmoon1968.
Source Firkin
This pattern comes in orange, and it looks as if it is "made of glass".
Source V. Hartikainen
Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Prismatic Polka Dots Mark II 2 No Background
Source GDJ
Prismatic Geometric Pattern Background 2
Source GDJ
A criss-cross pattern similar to one I saw mown into a sports field.
Source Firkin
Bumps, highlight and shadows – all good things.
Source Badhon Ebrahim
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
First pattern tailor-made for Retina, with many more to come. All the old ones are upscaled, in case you want to re-download.
Source Atle Mo
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
This is the remix of "Tileable Wave Pattern 2" uploaded by "Arvin61r58".Thanks.I added a wire-mesh fence seamless pattern as a lower layer.
Source Yamachem
Prismatic Polyskelion Pattern No Background
Source GDJ