[Leica] weight difference with lens

["F.Tjandra" <anfas@indosat.net.id>]

Recently I bought a used Summilux 35mm/f1.4 Titanium lens.Without filter
or lens hood, I  check out the weight of the lens on an electronic
jewellery scale.It weights 223.33gr (0.49lb).According to the Leica M6
brochures and the Leica M Compendium by Eastland , the weight for the
titanium lens is 195.00gr (0.43lb).It seems that there is more than 11%
weight difference! Is this normal? I check my other R lenses with the
same scale and they are the same or very close to the book's figures.
Next, I used a 6x loupe(can't see it with the naked eyes) to check tke
srew heads. I found out that two out of three screws on the furthest
front chipped(like marks left over from over tightening with the screw
driver). There is another one screw that fasten the aperture scale has
this same mark.I doubt that they came out from the factory in this
condition.What is your opinion?
As I look through the lens with wide aperture against a light source
(the usual buying used lens procedure ) I could not see anything unusual
i.e. clean glass from the front or the back.When I check the inner glass
from the back with the 6x loupe, I SAW a mass of very thin lines ( f
iber-like ) spreading all over the inner surface.I could not tell what
are those as there are small sratches also which I can see because they
reflect light differently.
I just like to figure out why the outermost glass are smooth and clean
but inner ones has all these extras.
I THANK YOU for your opinion.
Tjandra