Posted 03/14/2020 2:56 pm
I would add that the edge was applied to the planchet BEFORE the coin itself (obverse and reverse) was struck in an open sided screw press.
The edge mill (referred to in the US as a Castang machine) applies the edge by rotating the planchet between two parallel steel bars. One die is fixed and the second bar travels parallel to the first.
The edge design itself consists of alternating rectangles and circles. These features should be identical - circles match circles and rectangles match rectangles. Alignment should be close to a straight line and wobble of the design side to side on the edge should be limited. Spacing should be very close to uniform and the circles should be fully round. The only exception is the possible flattening of one side of the circle (facing either the obverse or reverse face) and never on both sides or the sides of the circle facing the rectangles.
Because two parallel dies are used there should be only two overlaps in the design of IDENTICAL length and occurring precisely opposite one another (180 degrees apart).
The length of each overlap can vary, however it should not exceed 3 segments on a typical die.
Long overlaps or odd numbers of overlaps are an indication of a fake. An over lap of 4 segments is highly suspicious and such a coin should be examined more closely with a Specific Gravity or XRF test.
If you can please post pictures of all three sides of the coin - obverse -reverse and edge. Please include photos of the edge overlaps taken on a slight angle so that the same face of the coin shows in each picture.
The edge mill (referred to in the US as a Castang machine) applies the edge by rotating the planchet between two parallel steel bars. One die is fixed and the second bar travels parallel to the first.
The edge design itself consists of alternating rectangles and circles. These features should be identical - circles match circles and rectangles match rectangles. Alignment should be close to a straight line and wobble of the design side to side on the edge should be limited. Spacing should be very close to uniform and the circles should be fully round. The only exception is the possible flattening of one side of the circle (facing either the obverse or reverse face) and never on both sides or the sides of the circle facing the rectangles.
Because two parallel dies are used there should be only two overlaps in the design of IDENTICAL length and occurring precisely opposite one another (180 degrees apart).
The length of each overlap can vary, however it should not exceed 3 segments on a typical die.
Long overlaps or odd numbers of overlaps are an indication of a fake. An over lap of 4 segments is highly suspicious and such a coin should be examined more closely with a Specific Gravity or XRF test.
If you can please post pictures of all three sides of the coin - obverse -reverse and edge. Please include photos of the edge overlaps taken on a slight angle so that the same face of the coin shows in each picture.
