#2-Ventifact - Taranaki - gifted by a geologist

A ventifact is a rock that has been abraded, pitted, etched, grooved, or polished by wind-driven sand or ice crystals. Wikipedia


 Stones that have been sculpted and polished by long-term exposure to abrasive wind-driven sands are called ventifacts—from the Latin “make by wind”.
Ventifacts are commonly mistaken for the artefacts of stone-age people, and indeed this piece resembles a knapped spear-point. Extraterrestrial origins have also been suggested: ie that such items are a form of meteorite.
Although this piece was found in Taranaki, this type of stone is from the South Island and may have been transported to the North Island during past glacial periods, over 20,000 years ago. During these times of lower sea level, the North and South Islands were joined between Nelson and Taranaki by a land bridge - and gravel from the South Island is thought to have drifted northward up that now-severed coastline.
Oddly, Sea Lions provide another way in which such “exotics” can be transported. The animals are known to swallow stones to aid their digestion and witnesses have reported seeing sea lions at rest on land regurgitating piles of stones weighing several pounds. Such stones are known as ‘gastroliths’ and Sea Lions, in their role as geological agents, can transport pieces of rock hundreds of kilometres from their original source.
From: www.nzgeo.com › stories › ventifacts-sandblast-from-the-past

Below - NZ geologist with large ventifacts:


 

Images below from:

https://www.sciencedirect.com/science/article/pii/S1631071313000369#fig0055




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