Yes, you want a souvenir of your vacation but do not remove any lava rocks. As superstition goes; removal of the rocks angers the volcano goddess Pele and brings bad luck to the person. So just go buy a souvenir from ABC...
"Take only pictures; leave only footprints." "Take only gifts you are given (like flower lei’s); and leave only with Aloha."
It's always important to be aware of the sun. Relaxing on a beautiful beach with a breeze can make you easily forget to check you skin for signs of a sunburn. We always slather on the sunblock; usually SPF 100 and make sure to re-apply requently. Liz and I both brings hats to ensure our faces do not fry in the sun.
The best thing to do is avoid peak burn times that are from 11am-3pm. We usaully get ourselves some lunch, drinks and shopping during this time to avoid getting crispy.
if you walk into a building and you are the only haole. get out because most locals hate you this is coming from a hopa with a grandma whom is an ancient but the younger generation for the most part no longger wants to be part of the states and their are rebel groups in the hills i am not like that so now you have been warned
A common warning intended to keep you from harm is 'Do not leave anything you care about losing in the car (not even locked in the trunk)'. This is good advice. However, my warning would be to remember that you are the visitor/foreigner ('haole') to this island. Treat the local people, the land, and the ocean with respect. With not always the best intentions, we (the visitors), over the past 200 years or so, have managed to change significantly the fragile landscape of these islands.
Not too much to worry about here. Common sense should keep you worry free. Don't leave your bags unattended on the beach, etc.