What it is
A clipped planchet coin is missing a curved or straight piece of its edge because the blank was cut from an overlapping or incomplete section of metal strip.
What causes it
The blanking press punched into an area already punched, or past the end of the strip.
How to identify it
- A curved clip matches the curve of another blank; a straight clip comes from the end of the strip.
- The design opposite the clip often shows weakness, called the Blakesley effect.
- Metal flows slightly toward the clipped edge.
How to tell it from damage
A piece cut off with tools leaves sharp edges and no Blakesley effect on the opposite rim.
How blanks are punched and where clips come from
Planchets begin as long coils of metal strip rolled to the thickness of the finished coin. The strip is fed through a blanking press, which uses a set of punches to stamp out many round blanks at once and leaves behind a strip of scrap full of holes called webbing. If the strip does not advance far enough, a punch comes down partly on an area that was already cut and the blank it produces has a curved bite missing. If the press punches past the end of the strip, the blank is missing a straight or ragged section.
After blanking, the blanks are annealed, cleaned and run through the upsetting mill, which squeezes the edge to raise a rim. Sorting screens called riddlers are meant to remove blanks that are the wrong size or shape, but clipped blanks that are close to the correct diameter in one direction can slip through and go on to be struck.
Types of clips
Curved clips, the most common type, are named for the arc of the missing piece, which has the same curve as a normal blank. Straight clips come from the leading or trailing end of the strip and have a straight edge. Ragged clips also come from the end of the strip, where the metal edge was rough or torn.
A blank can carry more than one clip when it was punched from a crowded area of the strip. Collectors call these double, triple or multiple clips. They can produce dramatic shapes. Very large clips that take away much of the blank leave a crescent-shaped coin with only part of the design.
Collectors also describe the size of a clip by the share of the coin that is missing (as with off-center strikes) and note whether the clip touches important design features such as the date or the mint mark.
The Blakesley effect and other signs of a real clip
The Blakesley effect is the most reliable sign. On a normal blank, the upsetting mill presses the edge evenly all around to form the rim. A clipped blank has a gap in its edge, so the mill cannot push properly against the area directly opposite the clip and the rim there stays weak. When the coin is struck, that area shows a flat or missing rim roughly 180 degrees from the clip.
Metal flow gives a second sign. During the strike, metal next to the clip has no rim or collar to hold it back, so it flows out toward the gap. Letters and the rim near the clip look slightly stretched, the rim tapers away as it approaches the clip and the design fades out with softened, rounded ends.
The clipped edge itself tells a story too. A genuine clip edge has the same texture as the rest of the edge, with a smooth sheared band and a rougher zone where the metal fractured as the punch went through. It is never sharp, polished or shiny like a fresh cut.
How fake clips are made and caught
Altered clips are cut with shears, nippers, files or grinders after the coin has been struck. A sheared fake leaves a sharp, often slightly bent edge with tool marks. A ground fake shows parallel scratches across the cut. Because the coin was struck as a full, round planchet, the rim opposite the cut is normal, there is no Blakesley effect and the design runs straight into the cut with no metal flow. On a fake, letters end abruptly at a crisp line. On a real clip, letters fade into the clip.
Weigh the coin and estimate the missing area. A genuine clip weighs less than normal in proportion to the size of the clip. A coin that is light but shows no Blakesley effect and has a tool-marked edge has been altered.
Examining a clip step by step
Hold the coin edge-on under a lamp and check that the clipped edge has the same sheen and texture as the rest of the edge. Turn to the rim opposite the clip and look for weakness or a missing section of rim. Look closely at the design nearest the clip for flow lines and fading letters. Weigh the coin on a scale that reads to a hundredth of a gram.
For a straight clip, check that the edge is truly straight and shows the rolled surface of the strip end rather than saw or file lines. For a ragged clip, the edge should be irregular but rounded and smooth, not jagged with fresh, bright metal.
Grading and attributing clipped coins
Grading services label these as clipped planchet errors and often specify curved, straight, ragged or multiple clips, sometimes with an estimated percentage. Larger clips, multiple clips and clips on scarcer denominations draw the most interest. A small curved clip on a common cent is one of the easiest genuine errors to find and makes a good first error for a new collector.
Frequently asked questions
What causes a clipped planchet?
The blanking press punched into an area already punched, or past the end of the strip.
How can I tell a clipped planchet from damage?
A piece cut off with tools leaves sharp edges and no Blakesley effect on the opposite rim.
How can you tell if a clipped coin is real?
Look for the Blakesley effect, a weak or missing rim directly opposite the clip. Also look for metal flowing toward the clipped edge. A tool-cut fake has a sharp edge, a normal opposite rim and a design that ends abruptly at the cut.
Why does a clipped coin weigh less?
Part of the planchet was never there, so the coin is lighter in proportion to the size of the clip. A coin that is light but fully round has more likely been worn or altered.
What is the difference between a curved clip and a straight clip?
A curved clip comes from a punch that overlapped a hole already cut in the strip, so the missing piece has the curve of another blank. A straight clip comes from the end of the strip.