TABLE VIII
Degrees of Hardness of Gem-Stones
| 5. | Kyanite (5–7), apatite, lapis lazuli |
| 5½. | Enstatite, beryllonite, sphene |
| 6. | Opal, moonstone, turquoise, diopside |
| 6½. | Spodumene, peridot, garnet (demantoid), benitoite, idocrase, epidote, axinite, jade (nephrite) |
| 7. | Iolite, quartz, tourmaline, jade (jadeite) |
| 7¼. | Garnet (hessonite, pyrope) |
| 7½. | Beryl, garnet (almandine), zircon, phenakite, euclase, andalusite |
| 8. | Topaz, spinel |
| 8½. | Chrysoberyl |
| 9. | Corundum |
| 10. | Diamond |
TABLE IX.—Data
Densities of Water and Toluol at Ordinary Temperatures
| Temperature | Water | Toluol | |
|---|---|---|---|
| Centigrade | Fahrenheit | ||
| 14° | 57·2° | 0·9994 | 0·8697 |
| 15° | 59·0° | 0·9992 | 0·8687 |
| 16° | 60·8° | 0·9990 | 0·8677 |
| 17° | 62·6° | 0·9988 | 0·8667 |
| 18° | 64·4° | 0·9986 | 0·8657 |
| 19° | 66·2° | 0·9985 | 0·8647 |
| 20° | 68·0° | 0·9983 | 0·8637 |
| 21° | 69·0° | 0·9981 | 0·8627 |
| 22° | 71·6° | 0·9979 | 0·8617 |
| 23° | 73·4° | 0·9977 | 0·8607 |
| 1 English carat | = 0·2053 gram |
| 1 Metric carat | = 0·2000 (one-fifth) gram |
| 1 oz. Av. | = 28·35 grams |
| 1 lb. Av. | = 0·4536 kilogram |
| 1 inch | = 25·4 millimetres |
| 1 foot | = 0·3048 metre |
| 1 yard | = 0·9144 metre |
| 1 mile | = 1·6093 kilometre |