This jewel appears to be nothing more than a well-cut stone of not less than 5,000 gp value. If magic is detected for, the gem will radiate a faint aura of the enchantment sort. 

If any character possesses the item, he or she will begin to feel its power after keeping the gem on his or her person for one week. At the end of two weeks, the individual will discover that he or she is able to understand things more easily, have better insight, memory, recall, etc. In fact, possession of the gem on a continuing basis (3 or more months) raises the Intelligence and the Wisdom of the character by 1 point each. 

If for any reason the gem is not kept beyond the 3-month period or longer, the additional Intelligence remains, but the 1 point of additional Wisdom is lost. 

Any one such gem will function but once every 50 years. 

If a character possesses a second gem after benefitting from one already, the second item will not increase either Wisdom or Intelligence, even if Wisdom was not permanently affected by the first gem.