General Facts
Colors
Gold Dragons
Golds are the leaders of the Weyr, in a sense. The Weyrwoman and her juniors make a great deal of the decisions involving what happens to the Weyr. Gold dragons are always female and impress to heterosexual female candidates. A gold dragon can clutch anywhere from ten to fifty eggs each clutch. Golds tend to be the largest dragons, ranging from 55-60 feet in length. They do not chew firestone -- doing so causes them to vomit the greyish mixture up harmlessly (though it smells rather foul.) Their riders do use flamethrowers to catch thread that evades the rest of the Weyr's wings though. Their colors range from dark burnt gold to pale, almost white.
Bronze Dragons
Bronzes are the co-leaders of the Weyr, though in a collective sense. Bronzes are the only dragons actively encouraged to fly golds (and so far are the only to have succeeded.) Bronze dragons are always male and impress to heterosexual male candidates only. Bronze dragons are the only dragons capable of siring a golden dragon egg and thus are integral to the continuation of the Weyr. Furthermore, a bronze can be elevated to the rank of Weyrleader on a whim, should he manage to capture a gold in flight. Overall, bronzes are the more fluid counterpart to golds -- just as important, but not as constant. Some Weyrs change Weyrleaders several times per turn. Bronzes range from 45-55 feet in length and can be anywhere from dark, greeny bronze to a brassy color.
Brown Dragons
Brown dragons are some of the least appreciated dragons in the Weyr. Capable of fullfilling almost rank, a brownrider has all the responsibilities of the other colors without the automated respect. In other words, a brown can take up nearly any position, from Wingleader to Weyrharper. Even Weyrleader is possible, although highly frowned upon. Brown dragons impress heterosexual and sometimes bisexual males. In extremely rare circumstances, browns -may- impress to homosexual females as well. To date this has happened only once. Browns are always male, regardless. They range from 40-50 feet in length and from near-black to tan.
Blue Dragons
Blues are reknowned for being some of the most versatile dragons. Although in truth browns are more deserving of this adjective, blues still have quite a bit of opportunity afforded to them. A bluerider can live his life out simply as a Wingrider, or he can choose to ascend to a higher rank. Either way, a bluerider isn't necessarily expected to advance as much as the other male colors -- it's all a matter of choice. Blue dragons are always male and can impress to male candidates of any sexuality. Bisexual and homosexual females also rarely impress to blues. One role blue dragons do fill is that of searchrider, given their seemingly heightened empathy. Blue dragons can be from 35-40 feet in length and range in color from dark navy to pale sky blue.
Green Dragons
Greens are second only to browns when it comes to being underappreciated. The working force behind a wing, Pern would fail without their speed and agility. Their ability to chew firestone renders them genetically infertile, as hoped by the original engineers of the dragons. Thus, even a green that has never chewed stone will be infertile. Greens are always female and can impress to anyone of any gender or sexuality. They are small, ranging from 30-35 feet, and colorwise range from dark green to jade.
White
There is limited knowledge of whites. Ruth was never exactly "studied" and has long since passed away. Although fleeting references may be made to the legendary beast, nobody expects one to hatch again. Which is good, because none ever will.