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
Derived from a drawing in 'Elfrica. An historical romance of the twelfth century', Charlotte Boger, 1885
Source Firkin
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
This one is amazing, truly original. Go use it!
Source Viahorizon
Like the name suggests, this background image consists of a pattern of dark bricks. It may be an option for you, if you are looking for something that looks like a brick wall for use as a background on web pages. It's not a masterpiece, but looks pretty nice when is tiled.
Source V. Hartikainen
Light gray pattern with an almost wall tile-like appearance.
Source Markus Tinner
Super detailed 16×16 tile that forms a beautiful pattern of straws.
Source Pavel
You could get a bit dizzy from this one, but it might come in handy.
Source Dertig Media
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamlessly tile-able grunge background image.
Source V. Hartikainen
To get the repeating unit, select the rectangle in Inkscape and use shift+alt+i
Source Firkin
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
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Remixed from a raster on Pixabay, that was uploaded by ArtsyBee.
Source Firkin
Background pattern made in "Grunge-Like" style. Available in both SVG and JPG formats. Edit to your needs then click the download button.
Source V. Hartikainen
This light background pattern has a texture of "frozen" surface with diagonal stripes. Here's an yet another addition to the collection of free website backgrounds.
Source V. Hartikainen
To get the tile this is made up from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Inspired by a drawing seen in 'City of Liverpool', James Picton, 1883.
Source Firkin
Simple wide squares with a small indent. Fits all.
Source Petr Šulc.