Punalu'u Beach

A.K.A The black sand beach.

What is the Black Sand beach?

Punaluʻu Beach is a beach between Pāhala and Nāʻālehu on the Big Island of the U.S. state of Hawaii. The beach has black sand made of bassalt and created by lava flowing into the ocean which explodes as it reaches the ocean and cools. Punaluʻu is frequented by endangered hawksbill and green turtles, which can often be seen basking on the black sand. The swimming area is very rocky, and it can be dangerous to swim. The beach also has a large amount of underground fresh water that flows in it. This fresh water is very cold and looks almost like gasoline mixing with the water.
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The Endangered species.

Hawksbill sea turtles are criticaly endangered turtles belonging to the family Cheloniidae. It is the only extant species in the genus Eretmochelys. The species has a worldwide distribution, with Atlantic and Indo-Pacific subspecies—E. i. imbricata and E. i. bissa, respectively The hawksbill's appearance is similar to that of other marine turtles. In general it has a flattened body shape, a protective carapace, and flipper-like arms, adapted for swimming in the open ocean. E. imbricata is easily distinguished from other sea turtles by its sharp, curving beak with prominent tomium, and the saw-like appearance of its shell margins. Hawksbill shells slightly change colors, depending on water temperature. While this turtle lives part of its life in the open ocean, it spends more time in shallow lagoons and coral reefs. Human fishing practices threaten E. imbricata populations with extinction. The World Conservation Union classifies the hawksbill as critically endangered. Hawksbill shells were the primary source of tortoiseshell material used for decorative purposes. The Convention on International Trade in Endangered Species outlaws the capture and trade of hawksbill sea turtles and products derived from them.
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Plants and Vegetation

The native plant communities generally appear as a narrow strand of vegetation, mostly a flattened growth of various shrubs, vines, grass-like plants, scattered trees and herbs. The varied habitats of pāhoehoe (smooth, ropy lava), and ʻaʻā flats, drifted sand, anchialine pond shores, protected beaches, and sea spray battered bluffs each support different native plant communities. In the reconnaissance survey, fourteen species of coastal strand plants (six trees, seven ground cover or shrub forms and the invasive aquatic water hyacinth). Native plants such as ilima (Sida fallax), naupaka kahakai (Scaevola taccada), and pōhuehue (Ipomoea pes-caprae brasiliensis) were found in the area.
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Where is it?

The beach is located at coordinates 19.136°N 155.504°WCoordinates: 19.136°N 155.504°W Latitude. Access is from the Hawaii Belt Road: take Ninole loop road or the entrance to the Sea Mountain Resort. Camping is permitted at the Punaluʻu Black Sand Beach Park. Making it a secondary coast line. Also featuring volcanic, marine forces and rising relative sea level since its existance from a submergent coast.
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What is Black Sand itself?

Black sand is sand that is black in color. One type of black sand is a heavy, glossy, partly magnetic mixture of usually fine sands, found as part of a placer deposit. Another type of black sand, found on beaches near a volcano, consists of tiny fragments of basalt.


While some beaches are predominantly made of black sand, even other colour beaches (e.g. gold and white) can often have deposits of black sand, particularly after storms. Larger waves can sort out sand grains leaving deposits of heavy minerals visible on the surface of erosion scarps.


Black sands are used by miners and prospectors to indicate the presence of a placer formation. Placer mining activities produce a concentrate that is composed mostly of black sand. Black sand concentrates often contain additional valuables, other than precious metals: rare earth elements, thorium, titanium, tungsten, zirconium and others are often fractionated during igneous processes into a common mineral-suite that becomes black sands after weathering and erosion.


Several gemstones, such as garnet, topaz, ruby, sapphire, and diamond are found in placers and in the course of placer mining, and sands of these gems are found in black sands and concentrates. Purple or ruby-colored garnet sand often forms a showy surface dressing on ocean beach placers.

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