Rosemount United Cemetery is located in Allegheny, Pa. This is where Charles Taze Russell is buried. See
http://www.freeminds.org/history/cemetary.htm
There is a Masonic cemetery across the road, which has no connection to Rosemount. The Cross and the Crown on the pyramid structure was a religious emblem of the time used by other groups of the times besides the Bible Students. Those motifs can be seen in other cemeteries elsewhere and on graves of people who were not Bible Students. (Cross & Crown came to be debunked). The pyramid was thought by Russell and the Bible Students to be God's stone witness corroborating Biblical time periods (Isa. 19:19). This belief was later debunked by Rutherford et al in 1928.