At low frequencies and within limits, increasing the number of turns "N" improves "Q" because "L" varies as "N"2 while "R" varies linearly with "N". Similarly increasing the radius "r" of an inductor improves (or increases) "Q" because "L" varies with "r"2 while "R" varies linearly with "r". So high "Q" air core inductors often have large diameters and many turns. Both of those examples assume the diameter of the wire stays the same, so both examples use proportionally more wire. If the total mass of wire is held constant, then there would be no advantage to increasing the number of turns or the radius of the turns because the wire would have to be proportionally thinner.