guépard Rectangle Moins schreger lines in ivory poussière nécessaire produire
Clare Brown on Twitter: "Really really clear Schreger lines on this #ivory lady's cheeks today. Would prefer that they were on an elephant's cheeks though 😢 https://t.co/SBXINyK6YA" / Twitter
mammoth-vs-elephant-ivory | The cross-hatching Schreger line… | Flickr
Distinguishing Elephant from Ancient Ivory - BLADE Magazine
Ivory: Significance and Protection
How-To: Tell Mammoth Ivory from Elephant Ivory - Make: