No. The round silver Threepence is too small a coin to have a milled edge.
There are no "grooves" on a British 1 Penny coin. The edge is not milled.
All British 5 Pence coins have a milled edge. The larger pre-1991 5 Pence coins were withdrawn from circulation and demonetised in 1991. So, unless they are part of a Proof or Uncirculated mint set or are individual Proof or Uncirculated coins and in absolute mint condition, they have little or no value.
At 11mm in diameter, Silver Pennies were too small to be milled, they had a plain edge.
The Edge of Youth - 1920 is rated/received certificates of: UK:U
Wane is the uncut edge of a board that has been milled from a tree. Essentially it is the 'bark' edge so instead of having a square cut piece of wood you have the contour of the outer edge of the tree on one or both sides of milled board. Once the board is 'edged' or squared off then you have dimesional lumber.
The British 10 Pence has always been a coin since its first issue in 1968. 10 Pence (from 1968 - 1992) 28.5 mm diameter, weigh 11.31 grams and are made from 75% copper and 25% nickel. The edge is milled. Now demonetised and no longer legal tender. 10 Pence (from 1992 to present) 24.5 mm diameter, 1.85 mm thick, weigh 6.5 grams and are made from 75% copper and 25% nickel. The edge is milled.
From 1969, the Australian 50 cent coin, when it was reintroduced, had 12 sides so that there was a good visual distinction between the 50 cent, and the 3mm smaller 20 cent coins, and you could also feel the difference between the two coins.
All British 5 Pence coins should have a milled edge. I do not know about "rare", but it is certainly not how it was intended to be, and if there is one, there may be more. It would fall into the category of a minting error and may have some value above the usual. A reputable coin dealer may be able to advise and give a valuation.
Answer 1:its called scrub you scrub Answer 2: The roughened or designed edge of a coin is called the milled or reeded edge. The reeding was introduced to demonstrate that the edge of the coin had not been filed, saved or clipped. (Back when the metal of the coin carried its true worth). It continues today as an aesthetic device.The British numismatic term for the reeded ridged edge is "graining" and the reeds are called "crenellations".
There are a number of ways that people have referred to it but the two most common is known as reeding or a reeded edge or milling and a milled edge.
Another difference was that the 20-cent coins had a smooth edge while the other silver denominations featured a reeded, or milled, edge. Therefore 'none' is the answer.
The only George III coins with Britannia on the reverse are the Twopence, Penny, Halfpenny and the Farthing, but none of them had a milled edge. From 1797, the Penny was 36mm in diameter, the Twopence was 41mm in diameter and both coins were made from copper.