Hi, There are two places to look for this information but you won't find it online.
Vital records weren't required in California until 1907 even though it was astate 1850. I'd first contact the Nevada County Clerk-Recorder,=new.mynevadacounty.com/recorder/ . They have all the old records if they exist.
You can also contact the Doris Foley Library for Historical Research, mynevadacouny.com/library/index.cfm?ccs=603&cs=432 . Successful Searching!