This category lists coin dealers who specialize mainly in coins that have been certified by a third party grading service, as opposed to raw or uncertified coins. The coins are encapsulated in plastic holders with a certified grade.
The grading services provide a grade using a numerical and letter grading scale with p-1 the lowest and MS70 the highest. P=poor and MS= mint state. Additional information may be included as to special characteristics, ie error variates, "Full Bands" for Liberty Head dimes, "Full lines" for Franklin halves, etc. These coins are referred to as "slabbed", "slabs" or "certified".