Table 2. Amount of metal and mechanical properties of Glycera and Nereis jaws in comparison.

Jaw	H, GPa	E, GPa	Metal	wt %	H3/2/E
Nereis			Zn
Mean tip	0.54	9.8		8.0	0.040
Mean middle	0.53	8.5		2.3	0.046
Min.	0.39	7.5		0.8	0.028
Max.	0.75	11.8		12.5	0.057
Glycera			Cu
Mean	1.11	15.16		12.4	0.077
Min.	0.89	13.42		0.3	0.063
Max.	1.31	17.75		29.6	0.084

Minimum (min.), maximum (max.), and mean values are given for hardness (H), elastic modulus (E), local metal concentration, and abrasion resistance (H^3/2/E).