Element Conductivity

Elements are arranged here in the associated graph by conductivity v. atomic number. There is a pattern that emerges from organizing these elements by number that does not appear when arranged in the usual periodic table layout. Particularly noticeable is the repeating structure denoted by Cu and highlited in blue. The highlited blue structure of the peak associated with Copper can be overlayed on top of the other three main peaked structures (denoted on the graph by Al,Ag and Au) and make exact matches . In other words each of the 4 peaks and their associated structures are similar in profile to the other 3.For instance in the Copper feature on the graph there are 3 other subsidiary peaks at Ca(20)Co(27) & Cr(24). each of these three seems to have corresponding matches in the other sets. For instance the Ca peak feature from the Cu set has matches in the other 3 sets of Be, Rb/Sr and Yb. Or the Co feature from the Cu set has matches from the other sets of Na/Mg,Rh and Ir.I have compiled these into 4`subsets` as follows.

Set 1) Cu, Al, Ag, Au

Set 2) Ca, Be, Rb/Sr, Yb

Set 3) Co, Na/Mg, Rh, Ir

Set 4) Cr, -, Mo, W

It would be of interest to see if each of these above 4 subsets of elements have any other properties that are common to that subset only. For instance do Ca,Be Rb/Sr and Yb share anyparticular common property unique to that subset alone or even in relation to the whole periodic table?