Tarsacci MDT 8000 On Black Sand In New Zealand

[phrunt]

I've had an interest in the Tarsacci for a while now, not enough of an interest to want one but more so an interest in what it's capable of.

We have some of the worst or best depending on how you look at it black sand beaches in the World in New Zealand.  I stumbled across a video of a person using their Tarsacci on a black sand beach near New Plymouth on the North Island.  New Plymouth is right under Mount Taranaki which is an active volcano and is a source of the black sand on New Zealand's North Island's west coast beaches.

Some information on the beaches from a government website

Scientists like Dr Hume can trace the origins of sand from the different proportions of minerals it contains. The snowy white sands of Parengarenga in Northland, for instance, are formed from quartz; while the golden sands of Golden Bay get their colour from the weathered iron (iron oxide) in granite. The black sand found on the west coast of the North Island, is made of titanomagnetite – a mixture of titanium and iron. This soft material comes from Mount Taranaki and is swept up the coast as far as North Cape – a distance of about 400 km – ground into rounder and finer grains as it goes.

“This is the biggest journey of sand anywhere in New Zealand, probably taking hundreds or thousands of years” says Dr Hume. “The sand is moved along this coastal highway by the prevailing waves that drive north from the southern ocean, stopped by headlands – ‘temporary carparks’ – along the way. The big sandpit at the end is Pandora Banks, a series of shoals off North Cape.”

Waves do most of the work moving sand; tidal currents do very little. Wherever there’s white water, sand is being bounced along the seabed. As any surfer will know, the wave energy on the west coast is very high, so it winnows out the less dense (and lighter-coloured) quartz and feldspar sands, leaving the denser black ironsand behind.

Sand can travel thousands of kilometres over time. But how long does it take to make sand from rock or shell? This depends on the type and hardness of rock (or shell), and how fast it’s broken down by weathering in the soil and during its transport by rivers to the sea.

“Hard minerals like feldspar and quartz – the source of creamy coloured sand on many beaches north of Auckland and in the Bay of Plenty – take thousands of years to get ground down to sand. Shells are much softer and may only take tens or hundreds of years,” says Dr Hume.

“On some beaches, shell is the primary source of sand,” says Dr Hume. “Overharvesting of pipis and cockles in harbours and estuaries can mean sand is in short supply.” On the other hand, the invasion of the hard-shelled Pacific oyster in the Manukau Harbour has converted some sandy beaches to shelly beaches, because Pacific oyster shells take longer to wear down than the shells of native shellfish.

You can see there are many types of sand that give beaches around the country their characteristic appearances and feel. So next time you are on the beach, take a closer look at the sand and ponder its origins.

Here is her video.  The interesting thing about this detector is they claim they've made an 11x9 inch "NZ Coil", a coil specifically made for detecting on NZ's black sand beaches, this is it for sale at our local Tarsacci dealer.  https://www.dredgenz.co.nz/product/11x9-inch-tarsacci-nz-coil/

While this New Plymouth beach she's at is a black sand beach, it's not one of the really black beaches like these in the photos below, both are further up the North Island from where she's detecting.    I wonder how it goes on them.

I'm yet to find a video of it being used on a really heavy black sand beach.