This invention relates to the use of 1-decene/1-dodecene olefin mixture to produce high viscosity polyalphaolefins (PAOs) having a viscosity of from about 40 cSt to about 100 cSt at 100.degree. C. (ASTM D-445) and a number average molecular weight of between about 1200 to about 4000, particularly useful as lubricant base stocks.