From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Could remind you a bit of those squares in Super Mario Bros, yeh?
Source Jeff Wall
High detail stone wall with minor cracks and specks.
Source Projecteightyfive
A seamless pattern formed from a tile made from ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
The image is a seamless pattern which is derived from a vine .Consequently, the vine got like dots via vectorization.The original vine is here:jp.pinterest.com/pin/500744052301410188/
Source Yamachem
This pack of filters can help you adding a blocky overlay to objects. May come handy at drawing blocks of stone.
Source Lazur URH
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Stefan is hard at work, this time with a funky pattern of squares.
Source Stefan Aleksić
Like the name says, light and gray, with some small dots and circles.
Source Brenda Lay
You don’t see many mid-tone patterns here, but this one is nice.
Source Joel Klein
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
More leather, and this time it’s bigger! You know, in case you need that.
Source Elemis
From a drawing in 'Prose and Verse ', William Linton, 1836.
Source Firkin