Trivia GMs and some players might care about.

Here is something I think every Game Master might care about and should be found in more RPG books. That way you can point to more than DM fiat as to why the golden statue of the goddess Anphribita can't be removed from the ransacked palace.

Average Weight of One Cubic Foot of Various Materials in lbs

Aluminum	162
Anthracite (Hard Coal); solid	93
Anthracite; loose	54
Ash	38
Brass; cast	504
Brass; rolled	524
Brick; pressed	150
Brick; common	125
Brick; soft	100
Cherry; dry	42
Clay; dry	119
Coal (soft); solid	84
Coal (soft); loose	49
Coke; loose	26
Concrete	154
Copper; cast	542
Copper; rolled	548
Cork	15
Earth; common loam	76
Earth; moderately rammed	95
Earth; flowing mud	108
Ebony; dry	76
Elm; dry	35
Flint	162
Glass; common window	157
Gneiss (rock); common	168
Gold; cast pure or 24 ct	1204
Gold; rolled hammered	1217
Grain at 60lb. per bushel	48
Granite	170
Hemlock; dry	25
Ice	58.7
Iron; cast	450
Iron; wrought	485
Iron; average	480
Ivory	114
Lead	711
Lime; quick ground or loose	53
Limestone and Marble; solid	168
Limestone and Marble; loose	96
Magnesium	109
Mahogany	53
Masonry; granite, limestone	165
Masonry; mortar rubble	154
Masonry; dry rubble	138
Masonry; sandstone	144
Mortar, hardened	103
Mud; dry	80-110
Petroleum	55
Platinum	1342
Salt; coarse	45
Sand; loose	90-106
Sandstone; for building	151
Silver	655
Slate	175
Snow; freshly fallen	5-12
Snow; moistened	15-50
Steel	400
Sulphur	125
Tar	62
Tin; cast	459
Turf or Peat; dry	20-30
Water; pure at 60F	62.3
Water; sea at 60F	64
Wax; bees	60.5
Zinc	437.5

This table came from Computing Tables and Formulas E.H. Barker 1913