It doesn''t look like a pear to me, although admittedly it doesn''t look like any other shape either! It looks squared off on the end away from her and more pointy towards her...but I can''t make out anything other than it''s massive! Looks like her biker dude went all out!!!
a "vintage engagement ring - a 1910 Tiffany and Co. piece from jeweler Neil Lane''s private collection. The setting of the two square diamonds symbolizes ''2 people in union'', says Lane, who also made Bullock''s wedding band."
MSNBC says this:
"Neil Lane helped the groom design a vintage-inspired engagement ring with the theme of “You and Me,” that had two intertwined diamonds and a diamond pave wedding band for his bride. Bullock made James'' wedding band herself out of stainless steel at James'' bike shop."