Toughness - resistance to breaking, chipping,
*Diamond has directional hardness not toughness,
Stability - resistance to chemical breakdown. Or color change due to variation in temperature.
Ultrasonic- Diamond no reaction
Acid- Diamond no reaction
Alcohol- Diamond no reaction
Ultrasonic- Pearl bubbles <attacked>
Acid- Pearl Attacked
Alcohol- Pearl in time will attack
*Diamond only mineral with covalent bonding
Fun TIP: Diamond in 850 degrees celsius diamond burns in air only outside of diamond burns, a cloudy appearance of burntness.
HARDNESS, TOUGHNESS, & STABILITY ALL = <*DURABILITY*>
Specific Gravity/ 3.52
Transparency/ very clear
Specific Gravity/ 1.20
Transparency/ Opaque (not see through)