@chinita and helga -- our guide said it's manmade daw. in my understanding, ganun nga, they just took sands from another part of marinduque and poured them there. the sand is white naman. but i dont suggest swimming there.
you can do island hoppning din whilst there. super pricey lang [textspeak!]
ng place but the service was superb.
if you want beach talaga, i wouldn't recommend this place.