This Coin I Don't If Real Or Fake? Please Help

The best way to tell silver from aluminum is weight. The density of silver is, almost, 4x greater.

Density of aluminum = about 0.1lb/cubic inch.
Density of silver = about 0.38lb/cubic inch.

One way is to figure out the density of the coin. The other is to find a silver coin which is about the size of that coin and to see if this coin weighs about the same amount in your hand.

It's a coin from the Dutch city of Kampen, an Arendschelling (eagle shilling), which is as you mention 6 stuiver. 30 mm is the size I'd expect, and they should weigh around 5 grams. It's not the nicest example, but from the photo I can't see anything that would indicate it's a fake. See here for some examples of fakes: http://www.nederlandsemunten.nl/Vir...tthias_I.htm Those have a weight around 3.5 grams, so just putting it on the scale could remove all doubt...

How do you get the year 1616 by the way?

If the weight is normally around 5 grams, then 5.2 is an acceptable deviation from that number. Now, there is only one thing you have to check based on qxy information. See if the coin has a diameter of 30mm. If it does, then your coin is real.

One catalogue I have puts the weight at 5.27 gram, and another at 4.95. My own coin of this type is 5.10 gram, so with 5.2 gram there is nothing wrong with the weight. Diameter is always less precise (to start with: the coins are never completely round, and often far from round...), but with 30 mm for your coin I have no reason to doubt its authenticity.

These coins are all struck without a year, and no precise dating is given in any of the catalogues I have. So the best thing to go by is the reign of Matthias, which is (from the top of my head) 1612-1619. Anything more precise is speculation, I think. :)