Reading from your 2nd link it seems more or less clrear:
"The silver printable coating on the CDR is designed to absorb ink-jet or other printer ink, prevent smearing, and provides higher quality in color printing".
So, if it is silver printable coating it must be the side opposite to the burnable side, if it is the upper surface or not it will depend how you look at the disc (just a joke...)
You can find gold burnable and depending on the dye, blue, green and silver looking surfaces. I don't know if there is some one that for marketing reasons they claim to be "silver coated"+