Bright gray tones with a hint of some metal surface.
Source Hendrik Lammers
Dark squares with some virus-looking dots in the grid.
Source Hugo Loning
Zero CC tileable hard cover green book, scanned and made by me. CC0
Source Sojan Janso
Colorful Floral Background 3 No Black
Source GDJ
Prismatic Isometric Cube Extra Pattern No Background
Source GDJ
It looks like a polished stone surface to me. Download it for free, as always.
Source V. Hartikainen
Inspired by a JPG that was uploaded to Pixabay by kokon_art
Source Firkin
Prismatic Floral Background No Black
Source GDJ
Original seamless pattern with an Inkscape filter.
Source Firkin
The tile can be had by selecting the rectangle in Inkscape and using shift+alt+i. Remixed from a drawing in 'Flowers of Song', Frederick Weatherly, 1895.
Source Firkin
Prismatic Rounded Squares Grid 4 No Background
Source GDJ
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Zero CC tillable hard cover red book with X shape marks. Scanned and made by me.
Source Sojan Janso