Recently I got a new coin which is one of my current favorites, a 1994 200 Escudos from Portugal, commemorating the 500 year anniversary of the Treaty of Tordesilhas. I found it interesting that there wasn’t a particular reason for getting this coin aside from the fact that Portugal is probably taking the third place in my heart among countries. In particular, because I don’t really collect commemoratives, though there are more and more exceptions to this rule lately. However, there’s no good reason why I like this coin, I just do, and I think it is part of collecting.
Numista provides an unusually detailed description of the coin:
Obverse
“2 ships, map of the Atlantic, Portuguese coat of Arms and value. The vertical line North-south represents the line of demarcation newly defined by the Treaty of Tordesillas (7 June 1494) that moved the previously defined line by 50 miles to the west. Portuguese expeditions were to stay east of this line, hence the underlined areas on the map of South America, future Brazil, and the Arms of Portugal on the map of Africa.”
Reverse
“Above the name of the treaty that led to moving the line of demarcation (defined by Pope Alexander VI in 1493) between Spanish and Portuguese areas to 370 miles West of the Cap Verde Islands (about 1770 km, 46°30′ West Greenwich). Portraits on the left=West of Isabel de Castilla and Ferdinand II de Aragon, Castillan flag, on the right= East, Joao II king of Portugal and flag.”
From a tactile perspective, this coin has the same problem that small coins do. The details are small. Usually on larger coins it is easier to feel the details, but this one is so dense with pictures related to the Treaty that the individual ones are hard to feel. Frankly, the only thing I was able to recognize is the north-south dividing line. Which is, well, a thin long line. Generally, when I read the description of a larger coin, it makes sense, at least parts of it. In this case, even when I knew what to look for, it was hard to recognize it.
And why do I still like it so much? First, because it is Portuguese. Recently I started reading more about the commemorative Escudos, and chances are I will sooner than later have the series. Second, this coin just feels unusually nice. Partly it has to do with the nice quality, though it would still be very interesting in a lower grade. Just feels very crisp, detailed, and though it is hard to figure out what the different objects are, one can feel that they are distinct and make up a whole.
I specifically got this coin, so I exactly knew what it is. I started to wonder what if I came across this one among hundreds of other coins, would I still be able to tell what it is without asking for assistance. So let’s see what are some ways I could narrow down what it could be. After careful examination, the number 200 can be found, but it is very small, and can easily be mistaken with 500. The next thing to check is weight and diameter. I have a kitchen scale, which is relatively precise, but it can’t measure fractions of grams. I got it for measuring food, but it had seen more coins than anything else. I checked the weight, it was 21 G, so let’s assume somewhere between 20 and 22. Probably the original coin weight is not very different, because this one has no wear on it. The diameter can be checked with a braille ruler, I still have it since I was a kid. It is metric based, which is an advantage in coin measuring. I can measure down to a half centimeter preciseness, and the rest can be estimated. It was approximately 35 MM, so let’s call it 33-37, though it is harder to measure, so unless the results contain an unreasonable amount of coins, I should work with 32-38. I can also make an assumption that it is not a very old coin, let’s be on the safe side and use 1900-2015. Now there is enough information to put into a Numista search. This is one of the best searchable catalogs, but it still doesn’t provide the flexibility I need, so we will worry about the metal later.
So far:
- Year: 1900-2015
- Weight: 20-22 G
- Diameter: 33-37 MM
This brings up a reasonable amount, 66 coins. Fortunately I don’t need to read through each of them to narrow it down further, the result page contains metal and alloy information, so I can just do a screen search and eliminate the ones which are definitely not a match.
The metal is hard to tell by touch, but there are certain things we know. It is not iron, this can be quickly checked with a magnet. Not pure aluminum, it would be much lighter, we specified a minimum of 20 g for weight. We are out of luck here, because none of the results contain aluminum, iron or steel in the metal description. It is not gold, because it would be much heavier, though none of the results contain gold obviously, same size gold coins would be heavier. It is not silver, we can tell by dropping it on the table. Silver coins have a very distinct sound. Now we can start narrowing the list down, out of the 66 coins 35 are silver. And practically this is where our elimination ends. An unusual result, the remaining coins are part of the Portuguese Escudo series, exactly 31 of them in this catalog. From this point, it would be much more difficult to figure out which one it is. If it was much less, it would probably make sense to continue, but at this point it would make more sense to ask somebody what it is, and spend the many hours saved on researching the background of this coin.
This research could be much easier if there was a catalog with a more complex search feature. For example, searching by edge type could further narrow down the search. Also, it would be nice to be able to exclude features as well, for example show me the coins which are not silver or steel. The other difficulty is that not all data is entered about all of the coins. For that matter, not all coins are entered. So, this search primarily assumes that the coin we are looking for is in the catalog, and contains all the data we are searching for. Otherwise, we may not end up with anything, or we would narrow it down to another coin that is something else.
I thought it would be interesting to have this elimination process described on the blog, I previously wrote about it, but this is the way I am able to find what a certain coin is. Sure, I could ask, and often I do, but if I have time and the coin has enough distinct features, it is part of the fun.