Hints from over 50 years of collecting
; I have tried these.
-Never dip any copper/bronze coin or token in coin dip ! It will turn a strange orangey colour and will never ever, ever return to anything resembling a normal old cent ! Ever. Best thing to do with dipped old cents is to polish them, and use them to make some kind of display (nice inlays in a table-top maybe).
- Never use any detergent or soap on a cent. A man I worked with brought me a load of 1940-50's cents but he washed them with soap before. All had lost patina and looked too light- may retone.
-On cents and copper tokens, I use an old soft toothbrush. Start with just water. That's usually all you'll need; water and brush, simple. Don't scrub, just brush. The brush will not scratch bronze (I tried it on a red pre-65 cent and could not see any hint of scratching with a 10x loupe). On old brown ones, nothing, even with a 200x USB microscope camera. If there is corrosion, I use a bit of penetrating oil. If you do it for more than about 15-30 seconds per side it may start to take off patina with penetrating oil. I have this oil because I buy lots of old colonial tokens or dug coins,and also soak old roman coins(need rubber gloves - corrosive, wrecked fingernails before gloves). Try lighter oils like margarine or vegetable oil on an extra coin and see if it gives any results. You can usually get all the crud stuck in the letters out but any corrosion will remain. Wash with hot water, you can rub dry with a cotton towel or T-shirt - they won't scratch copper.
-Don't use a brush on silver or brass.
-If you dip a silver coin, do it for the LEAST amount of time possible (10 seconds is usually good while swishing the liquid around). A gentle rub with a rubber-gloved finger, a long, running-water rinse, a cotton towel pat-down (not a rub), let sit to get to room temperature before putting it in a 2x2 so you don't get moisture trapped with it. Dip too long and it can go a dull grey, believe me, I've done it. (Tarn-X, any Canadian hardware)
-If there is a fingerprint mark, you're doomed ! Nothing can fix it.
-Coins didn't come from any mint covered in silver sulphide nor dirt. When you clean your car that is covered in dirt or mud, you are not enhancing it, you are simply bringing it back to it's original state.
-If in doubt, lick your thumb and rub.
Posted 03/02/2017 9:41 pm
