Each Weatherlight Booster Box contains 36 Weatherlight Booster Packs containing 15 random cards (1 Rare, 3 Uncommon, and 11 Common cards). There are 51 different Rares, 61 Uncommons, and 55 Commons in the entire set (it is not possible to build an entire set out of one box, but you do get 540 Weatherlight cards).
Released in June of 1997, Weatherlight was the eleventh Magic expansion, and is considered the third expansion of the Mirage Block. Containing 167 cards, Weatherlight is a standard-smaller sized expansion. This set is known for setting the stage for the Rath Cycle storyline. With the introduction of Gerrard and the crew of the Weatherlight ship, Magic would see the developtment of its first set-to-set storyline. So successful were Gerrard and his companions that the story of the Weatherlight would go on to write Magic history for many years.
Tournament players were very satisfied with this set; this expansion introduces Gemstone Mine (one of the best sources of all five colors of mana - pound for pound - in the industry), Null Rod (a well known vintage tournament artifact hoser), Gaea's Blessing (a mill decks worst nightmare), Buried Alive (many reanimator decks staple enabler), and Ophidian (Force of Will's other half in one of early Magic's most dominating combos).
There are several other cards worthy of mention from the Weatherlight set, several cards that further define this set are: Abeyance, Empyrial Armor, and Lotus Vale.