Hi Izarabal,
Welcome, the necklace appears to be genuine cultured freshwater white/ivory button pearls. The pearls have a nice lustre, nicely matched, not sure what size they are. Quality of knotting is good, too. Also unsure what the reddish gems are, they could be crystal or cubic zirconia. Clasp appears to be white metal, but can't see well enough to guess if it adds much value. With no additional information, I would put the overall value at no more than $45-50 retail. It definitely is an attractive design for a young woman!