The image depicts a seamless pattern of a snow crystal.I referred to a book called ”sekka-zusetsu” or "雪華図説" which means an illustrated explanation about snow crystals.This book was published in 1832 (天保3年) or Edo period.For more about "雪華図説",see here:dl.ndl.go.jp/info:ndljp/pid/2536975
Source Yamachem
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A seamless background of warped stripes on paper.
Source V. Hartikainen
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Kaleidoscope Prismatic Abstract No Background
Source GDJ
A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo
Prismatic Abstract Geometric Background 3
Source GDJ
Black brick wall pattern. Brick your site up!
Source Alex Parker
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Derived from an image that was uploaded to Pixabay by pugmom40
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Your eyes can trip a bit from looking at this – use it wisely.
Source Michal Chovanec
From a drawing in 'La Principauté de Liège et les Pays-Bas au XVIe siècle', Société des Bibliophiles Liégeois ,1887.
Source Firkin
I know there is one here already, but this is sexy!
Source Gjermund Gustavsen
A slightly more textured pattern, medium gray. A bit like a potato sack?
Source Bilal Ketab
Remixed from a drawing in 'The Canadian horticulturist', 1892
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
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Remixed from a raster on Pixabay, that was uploaded by ArtsyBee.
Source Firkin
Not strictly seamless in that opposite edges are not identical. But they do marry up to make an interesting pattern
Source Firkin
Same as gray sand but lighter. A sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Adapted from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Coming in at 666x666px, this is an evil big pattern, but nice and soft at the same time.
Source Atle Mo
Derived from an image that was uploaded to Pixabay by mdmelo.
Source Firkin
Prismatic Groovy Concentric Background 3
Source GDJ
I’m starting to think I have a concrete wall fetish.
Source Atle Mo