[Campaign Rules. There are two different kinds of spell books.]
These can contain up to 24 spells of under 4th level, 16 spells of under 7th level, or 8 spells of 7th, 8th, and/or 9th level.
A standard spell book costs 1,000 gold pieces for materials plus 100 additional gold pieces per spell level for each spell contained therein. The cost of a new magic-user’s or illusionist’s initial book or books is assumed to be borne by the new spell caster’s former master and these are always standard spell books.
A standard spell book is approximately 16 inches in height, 12 inches wide, and 6 inches thick. The weight of a standard book is 150 gold pieces (adjusted upward or downward for varying sizes). The encumbrance value of such a book is equal to three times its weight (450 g.p. or thereabouts), although it is correct to assume that a volume will fit within an otherwise empty backpack or large sack.
These slimmer volumes can contain, at most, one-fourth of the number of spells possible to be contained in a standard spell book: 6 spells of 1st, 2nd, and/or 3rd level; 4 spells of 4th, 5th, and/or 6th level; or 2 spells of 7th, 8th, and/or 9th level.
A traveling spell book costs 500 gold pieces for materials. The cost of each spell contained within such a book in the same as the cost for entering a spell in a standard book.
A traveling spell book is approximately 12 inches tall, 6 inches wide, and 1 inch thick; The weight of such a book is approximately 30 gold pieces, and encumbrance roughly 60 g.p.
Notwithstanding any special protections placed thereon, a standard spell book has a saving throw equal to that of “leather or book,” with +2 to dice rolls made to save against acid, fireball, disintegration, and lightning attacks. A traveling spell book is the same but receives no bonus.
A standard spell book has an experience point value of 500 points per spell level contained therein, and a gold piece sale value of 1,000 g.p. per spell level. As with any other magical items acquired, spell books must either be sold immediately or else the x.p. value taken. This holds true regardless of whether or not any tome is eventually sold. Thus, a spell book cannot be kept while a particular spell or spells are transcribed, and then the work sold for the gold piece sale value and the proceeds taken toward experience points.
Non-standard spell books, such as the scribbling of witch doctors or the like are worth half of normal (x.p. or g.p.).
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