Green sand beach gets its name from the green olivine crystals in the cinder cone which was formed 49.000 years ago next to the beach. If you are thinking about going there while visiting the Big Island have a look at our article on Green Sand Beach.
- The how and why of the 3 different names this beach is known for (Papakōlea, Mahana, and Green sand beach)
- Why the green sand is green (olivines!)
- How many green sand beaches there are in the world (chemical composition, crystal-to-sand ratio).
The different names of green sand beach
Green sand beach is officially named “Papakōlea Beach”, but is also known as Mahana Beach and of course… green sand beach. These names have the following background:
This name is a contraction of the words papa and kōlea. Papa means ‘flats’ and kōlea is the Hawaiian name for the Pacific golden plover. These birds can be found in this area during the winter, hence the name “Plover flats”.
The cinder cone on the west (right on the picture below) side of the beach is called the Puʻu Mahana. The green sand ‘particles’ on the beach are olivine crystals that formed during an eruption of the Mauna Loa 49.000 years ago
Green Sand Beach:
This name is self-explanatory and the most commonly used name for this beach on the Big Island. Read on to find out why exactly the sand is green at green sand beach.
Why is the sand at green sand beach, green?
Green Sand Beach gets its name from the green glassy crystals (Olivine) that make up most of the sand on this beach. Olivine is locally known as “Hawaiian Diamond” and is denser and tougher than the ash fragments, glass and black pyroxene of the rest of the rocks and lava flows.
The secret of Green Sand Beach is the unique combination of a 49.000-year-old cinder cone that spewed olivine-rich lava, together with a bay that keeps the olivine crystals that are washed out of the rocks, trapped. Olivine is quite heavy and tends to accumulate on the beach, whereas the lighter volcanic sand is swept out to sea. The ‘greenness’ of the beach then is a direct reflection of the ratio between the green olivine and the other sand-components.
How many green sand beaches are there in the world?
This question is actually pretty difficult to answer. If you go to Wikipedia, you will see that there are only 4 green sand beaches in the world (the other 3 green sand beaches are Talofofo Beach on Guam, Punta Cormorant on Floreana Island in the Galapagos Islands, and Hornindalsvatnet in Norway). But what exactly is a green sand beach?
Papakolea beach on the Big Island gets its color from a large amount of olivine crystals that are mixed into the sand, but there are many other beaches that contain less olivine and thus are “less green”, and even more that have green sand for reasons other than olivine crystals!
What is the reason behind these many shades of green?
How “green” the sand on a beach is, depends on the two following factors:
- Different chemical composition: Most green sand beaches have different shades of green, depending on the minerals that give them their color. Some examples of these ‘green’ minerals are: Glauconite, Malachite, Chlorite, Epidote, and Serpentine. You can find an illustrated article with photos of some of these beaches here.
- Different amounts of olivine: Olivine is a pretty common constituent of basalt (lava), and it can be found all over the Big Island and in many other volcanic regions in the world. You can for example easily find rocks with green olivine crystals in them when crossing the crater of the Kilauea’iki (one of our favorite short hikes on the Big Island) in the Hawaii Volcanoes National Park.
This means of course that there are also other “less green green sand beaches” on the Big Island (and worldwide), such as Richardsons ocean park in Hilo. You can find some green sand (olivines) on these beaches, but not in the amount one can find for example on Papakōlea beach.
What makes this beach special is that the sand of Papakōlea beach contains so many olivines. Because of its unique location in a narrow bay, the normal sand washes away to the ocean but the heavier olivines remain behind on the beach.
In summary, there are many shades of green when talking about green sand beaches, and to say there are “only four green sand beaches on the planet” is cutting a lot of corners. Having said that, Papakōlea beach on the Big Island is a unique beach with sand that has one of the highest olivine contents of the world! It’s safe to say that the Big Island is an amazing place :)
Our favorite white sand, black sand and green sand beach on the Big Island:
You can find out why white sand is white and why black sand is black at our hottest big island beaches article. In it we describe our #1 picks for beaches with sand that is green, black and white.