An attempt for cleaning up the original image in a few steps.
Source Lazur URH
It’s like Shine Dotted’s sister, only rotated 45 degrees.
Source mediumidee
Bright gray tones with a hint of some metal surface.
Source Hendrik Lammers
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Sharp diamond pattern. A small 24x18px tile.
Source Tom Neal
Medium gray pattern with small strokes to give a weave effect.
Source Catherine
ZeroCC tileable mossy (lichen) stone texture, edited from pixabay. CC0
Source Sojan Janso
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Here's an yet another seamless note paper texture for use as a background on websites.
Source V. Hartikainen
Derived from an image that was uploaded to Pixabay by pugmom40
Source Firkin
Paper model of a tetrahedron. Modelo de papel de um tetraedro.
Source laobc
Prismatic Groovy Concentric Background 2
Source GDJ
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Stefan is hard at work, this time with a funky pattern of squares.
Source Stefan Aleksić
Prismatic Groovy Concentric Background 4 No Black
Source GDJ
Lovely light gray floral motif with some subtle shades.
Source GraphicsWall