Scientific name: Wikstroemia indica C.A. Mey., Thymelaceae
Your necklace was made from this species. They are popular in Vietnam and currently not in danger in wild (extinct) so the price of them are quite low compared to other species (i.e Aquilaria Crassna, or Aquilaria malaccensis).
The aroma is very subtle compared to other Agarwood product but it is beautiful . Mixed in are turquoise gemstones, red (dyed) coral beads and Nepalese decorative beads.