Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Sounds French. Some 3D square diagonals, that’s all you need to know.
Source Graphiste
Formed by distorting the inside front cover of 'Diversæ insectarum volatilium : icones ad vivum accuratissmè depictæ per celeberrimum pictorem', Jacob Hoefnagel, 1630.
Source Firkin
Non-seamless pattern drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
Kaleidoscope Prismatic Abstract No Background
Source GDJ
This one has rusty dark brown texture.
Source V. Hartikainen
Prismatic Curved Diamond Pattern 3 No Background
Source GDJ
Same as Silver Scales, but in black. Turn your site into a dragon with this great scale pattern.
Source Alex Parker
Paper pattern with small dust particles and 45-degree strokes.
Source Atle Mo
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Beautiful dark noise pattern with some dust and grunge.
Source Vincent Klaiber
Can’t believe we don’t have this in the collection already! Slick woven pattern with crisp details.
Source Max Rudberg
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
An interesting dark spotted pattern at an angle.
Source Hendrik Lammers
Bright Multicolored Floral Background by Karen Arnold from PDP.
Source GDJ
If you’re sick of the fancy 3D, grunge and noisy patterns, take a look at this flat 2D brick wall.
Source Listvetra
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Alternative colour scheme. 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
Sharp pixel pattern looking like some sort of fabric.
Source Dmitry