Cutting errors - Clips

Elliptical clip

Cutting errors, specifically clips, are a type of coin error that occur when a portion of the planchet is accidentally cut out during the production process. This error can happen during the blanking process, when a circular disk is cut from the metal strip that will become the planchet. If the cutting tool overshoots or undershoots, a portion of the planchet will be missing, resulting in a clipped coin.

Clipped coins can vary in size depending on how much of the planchet was cut off. If a significant portion of the planchet is missing, the coin will be noticeably smaller and lighter than a normal coin. If only a small portion is clipped, it may be difficult to detect without close examination.
Clipping errors can also be caused by foreign objects getting in between the dies and the planchet during the striking process. This can cause portions of the planchet to be compressed and flattened, resulting in a clipped appearance.
In some cases, clipped coins may have other associated errors, such as double strikes or off-center strikes. These errors can add to the uniqueness and desirability of the coin for collectors.
Ragged clip
The coin error known as Ragged Clip occurs when the press punches shear the end of the metal coil during the minting process. This error is rare but can occur when an employee fails to stop the punching press in time due to negligence. The resulting coin will have a ragged or incomplete edge due to the missing metal portion caused by the shearing action of the press punches.
Straight clip
The straight clip is a type of coin error that occurs when the metal plate used in the punching press is narrower than normal. Due to this discrepancy, the metal plate fails to adhere to the lateral guides installed on the press and moves laterally, resulting in the punches cutting over the edge of the plate.
In the case of bimetallic planchets, the clip can be found on the outer ring or the core, and it can not be ruled out that it may also be found in a combined form with other types of minting errors. It is essential to note that straight clips can significantly affect the appearance and value of the coin, and collectors often seek them out due to their rarity and uniqueness.
Curved clip
Curved clip errors occur when the metal plate inside the punching press advances at a lower speed than the predetermined rate, causing perforation to take place on a section of the plate that was previously punched. To authenticate such errors, it is necessary to examine the edge near the two corners that coincide with the curved clip. A groove is often present near one or both corners due to the pressure exerted by the monetary press, and there may be an expansion or evanescence of the reliefs involved in the curved clip.
Another identifying feature is the Blakesley effect, named after the American expert who discovered it. This effect consists of a portion of a flat edge that always appears on the diametrically opposite side of the coin, generally of the same width as the pinched area. However, this effect is not always present in coins minted on curved clips. The flat edge is generated because the hemming machine can not exert the necessary pressure in the clipped area, causing the edge positioned diametrically opposite to the planchet to remain flat.
In the case of bimetallic coins, the clip may occur on the outer ring or on the core. This type of error can also be found combined with other types of errors. Furthermore, it may happen that the slab is perforated between two or more clips, creating double or triple curved clips on the planchet.