Why are so many rocks in Hawaii dark?
Why are so many rocks in Hawaii dark? In Hawai`i, we see almost nothing but igneous rocks. Most of those are black or gray when young or brown-to-red when old and weathered. The lava in Hawai`i owes its dark colors to a high iron and magnesium content. As it ages, oxidation of the iron creates the orange and red hues.
Can you swim in black sand beaches?
Swimming at Punalu?u is possible but be careful when going into the water because there can be strong currents at times. Bring water shoes if you have them because the black sand on the beach gets hot quickly in the sun and there are many rocks in the water that can be painful when stepped on.