Geometric triangles seem to be quite hot these days.
Source Pixeden
Prismatic Rounded Squares Grid 4 No Background
Source GDJ
This pack of filters can help you adding a blocky overlay to objects. May come handy at drawing blocks of stone.
Source Lazur URH
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Lovely pattern with splattered vintage speckles.
Source David Pomfret
A repeating background with dark brown stone-like texture and abstract pattern that looks like tree trunks.
Source V. Hartikainen
Light honeycomb pattern made up of the classic hexagon shape.
Source Federica Pelzel
You don’t see many mid-tone patterns here, but this one is nice.
Source Joel Klein
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
From a drawing in 'Royal Ramsgate', James Simson, 1897.
Source Firkin
Retro Circles Background 8 No Black
Source GDJ
Abstract Tiled Background Extended 6
Source GDJ
Did some testing with Repper Pro tonight, and this gray mid-tone pattern came out.
Source Atle Mo
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
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk
If you’re sick of the fancy 3D, grunge and noisy patterns, take a look at this flat 2D brick wall.
Source Listvetra
Geometric lines are always hot, and this pattern is no exception.
Source Listvetra
Bumps, highlight and shadows – all good things.
Source Badhon Ebrahim
Tile-able Dark Brown Wood Background. Feel free to use it as a background image in your designs or somewhere on the web. By the way, the color seems to be close to Coffee Brown.
Source V. Hartikainen
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
Not strictly seamless in that opposite edges are not identical. But they do marry up to make an interesting pattern
Source Firkin