Variety of colorful natural stones. Free public domain CC0 photo. https://www.rawpixel.com/image/6037453/photo-image-public-domain-black-background-redFree Image from public domain licenseVariety of colorful natural stones. Free public domain CC0 photo. https://www.rawpixel.com/image/6037450/photo-image-public-domain-black-background-redFree Image from public domain licenseDifferent types of birds illustrated by Charles Dessalines D' Orbigny (1806-1876) Digitally enhanced from our own 1892… https://www.rawpixel.com/image/324041/free-illustration-image-birds-vintage-featherFree Image from public domain licenseAmethyst sea holly from La Botanique de J. J. Rousseau by Pierre-Joseph Redouté (1759–1840). Original from the… https://www.rawpixel.com/image/573938/amethyst-sea-hollyFree Image from public domain licenseMeadow squill from Edwards’s Botanical Register (1829—1847) by Sydenham Edwards, John Lindley, and James Ridgway. https://www.rawpixel.com/image/559170/scilla-amethyst-meadow-squill-posterFree Image from public domain license