It looks like a polished stone surface to me. Download it for free, as always.
Source V. Hartikainen
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
Sort of reminds me of those old house wallpapers.
Source Tish
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Continuing the geometric trend, here is one more.
Source Mike Warner
Remixed from a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Zero CC tileable moss or lichen covered stone texture, edited from pixabay. CC0
Source Sojan Janso
A nice and simple gray stucco material. Great on its own, or as a base for a new pattern.
Source Bartosz Kaszubowski
Not so subtle. These tileable wood patterns are very useful.
Source Elemis
A simple circle. That’s all it takes. This one is even transparent, for those who like that.
Source Saqib
This is a semi-dark pattern, sort of linen-y.
Source Sagive SEO
Dead simple but beautiful horizontal line pattern.
Source Fabian Schultz
You know you love wood patterns, so here’s one more.
Source Richard Tabor
Geometric triangles seem to be quite hot these days.
Source Pixeden
Prismatic Groovy Concentric Background 5
Source GDJ
The tile this is based on was adapted from an image that was uploaded to Pixabay by frolicsomepl. It can be had in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
Zero CC tileable hard cover cells book texture, 4k, scanned and made by me. CC0
Source Sojan Janso