From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Just what the name says, paper fibers. Always good to have.
Source Heliodor jalba
Remixed from a drawing in 'A Child of the Age', Francis Adams, 1894.
Source Firkin
You can never get enough of these tiny pixel patterns with sharp lines.
Source Designova
This is so subtle you need to bring your magnifier!
Source Carlos Valdez
Colour version of the original pattern inspired by the front cover of 'Old and New Paris', Henry Edwards, 1894.
Source Firkin
Real snow that tiles, not easy. This is not perfect, but an attempt.
Source Atle Mo
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Colour version that is close to the original drawing uploaded to Pixabay by pencilparker.
Source Firkin
Small gradient crosses inside 45-degree boxes, or bigger crosses if you will.
Source Wassim
This one is amazing, truly original. Go use it!
Source Viahorizon
Prismatic Groovy Concentric Background 3
Source GDJ
A free seamless background texture of "timber wall" (colored in dark brown).
Source V. Hartikainen
Prismatic Snowflakes Pattern 2 No Background
Source GDJ
Small dots with minor circles spread across to form a nice mosaic.
Source John Burks
Square design drawn in Paint.net and vectorized in Vector Magic.
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
Prismatic Abstract Geometric Background 4
Source GDJ
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
Everyone loves a diamond, right? Make your site sparkle.
Source AJ Troxell
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Horizontal and vertical lines on a light gray background.
Source Adam Anlauf