I used points graphic (geoR) in this way:
points(zn,pt.divide=c("quintiles"),
main="Location map of Zn",lambda=1,col="gray",yl="coord y",xl="coord x",x.leg=0.
3, y.leg=5.5,dig.leg=2,cex.min=0.5,cex.max=1,)
Can I reduce legend characters
(a sort of cex)?