also called "reverse engineering" in technical jargon.
In contrast to CAD modelling, where there is an idea, a concept at the beginning and at the end of the process a finished real product (a piece of jewellery) is to be manufactured, here it is exactly the opposite.
The starting point is an existing real object (grandma's old ring, grandpa's signet ring with the family crest, small statuettes, etc.) that is to be reproduced and possibly modified.

With the 3D scanner, the object can be captured in 3D to create a virtual copy and output im STL format

With the scanned STL model, can create a digital copy of the original​

• CNC milling

• 3D printing

The following measurements can be carried out on this STL model

• longitude

• diameter

• surface areas

• volume

• angle

• etc

The STL model can be imported into CAD MatrixGold  and further edited:

• add to

• modify

• use details

• etc