Currents may also be generated by density differences in water masses caused by temperature and salinity variations. These currents move water masses through the deep oceanâtaking nutrients, oxygen, and heat with them. Occasional events also trigger serious currents. Huge storms move water masses.
Ray-ban and most other manufacturers frames are made from Plastic compounds. Ray-ban used to make all its glasses out of 'glass'. Now it makes its sunglass products out of scratch resistent plastics. Often they will 'feel' like glass but are in fact most usually plastic production.
It is possible to pick up wholesale eyewear made in China for around USD $2 a pair, excluding lenses. This is the very much cheaper end of the market, and it could be even less than this with the scale of Ray Ban. However, Luxottica a) make most of their eyewear in Italy (though for optical frames, a fair amount is starting to be made in China) and b) Ray Bans are better quality than $2 Chinese frames.