The heart is made with yellow gold plated silver 925 and this pendant features a round diamond that is prong set. The stones are VERY vibrant.  The chain is a 14k Yellow Gold Singapore Rope Chain, 20 inches long (I think 1mm thick - 4 grams total weight).  It is Italian Gold as shown in above pics.  I have worn these two pieces together for quite a few years and it is really a beautiful piece.  Difficult to capture the radiant stones in the pics.

Please contact me with any questions.