As far as fabric patterns goes, this is quite crisp.
Source Heliodor Jalba
Beautiful dark noise pattern with some dust and grunge.
Source Vincent Klaiber
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
A textured blue background pattern with vertical stripes.
Source V. Hartikainen
Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
And some more testing, this time with Seamless Studio. It’s Robots FFS!
Source Seamless Studio
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Subtle scratches on a light gray background.
Source Andrey Ovcharov
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
An alternative colour scheme to the original seamless pattern.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A dark pattern made out of 3×3 circles and a 1px shadow. This works well as a carbon texture or background.
Source Atle Mo
A pale orange background pattern with glossy groove stripes.
Source V. Hartikainen
The image depicts a seamless pattern of a Japanese family crest called "chidori" in Japanese .A chidori in Japanese means a plover in English.
Source Yamachem
Bumps, highlight and shadows – all good things.
Source Badhon Ebrahim
Colour version of the original seamless pattern.
Source Firkin