Watch this palaeontologist expose a 4-million-year-old crab fossil that was concealed in a rock he found on a beach in Paraparaumu, New Zealand.

The filmer, known as Mamlambo on YouTube, is seen meticulously removing sections of the rock using an air scribe.

He said: "A few weeks ago, I found this concretion on the beach containing a fossil crab. Part of the claw was exposed as well as sections of the legs. The fossils in this area are roughly 4 million years old based on estimates of the geological layer.

Talking about the process of exposing the fossil, he added: "The air scribe never touches the fossil itself as the tungsten carbide stylus would damage the fossil, rather the vibration cracks the rock and it falls away from the fossil as the fossil and matrix are different materials and textures.

"Some areas of the fossil are 'sticky' and require further preparation using a micro air abrasion kit which is like a small sandblaster. In this case, the dolomite powder was used to remove that last layer of the matrix to expose the fossil underneath.

Parts of the fossil, especially the legs, have turned to iron pyrite (fool's gold) which is very sparkly but can be difficult to prep.

"The solution painted on is B72 paraloid which consolidates the fossil and stops it from flaking as the air scribe has quite a powerful jet of air coming out the front.

"It took about five hours to prepare this fossil which is very quick compared to some of my other projects."

A few weeks ago, I found this concretion on the beach containing a fossil crab. Part of the claw was exposed as well as sections of the legs. The fossils in this area are roughly 4 million years old based on estimates of the geological layer.

Using an air scribe (which is like a mini jackhammer), the rock was removed to expose the carapace of the crab. The air scribe never touches the fossil itself as the tungsten carbide stylus would damage the fossil, rather the vibration cracks the rock and it falls away from the fossil as the fossil and matrix are different materials and texture.

Some areas of the fossil are "sticky" and require further preparation using a micro air abrasion kit which is like a small sand blaster. In this case dolomite powder was used to remove that last layer of matrix to expose the fossil underneath.

Parts of the fossil, especially the legs, have turned to iron pyrite (fool's gold) which is very sparkly but can be difficult to prep.
The solution painted on is B72 paraloid which consolidates the fossil and stops it from flaking as the air scribe has quite a powerful jet of air coming out the front.

It took about 5 hours to prepare this fossil which is very quick compared to some of my other projects.

Music is from bensound.com and requires attribution.