One nice but the metal makes less difference than you think because a really nice bronze costs the same as a silver. There are cheap bronzes but they usually are not as attractive because bronze often weathers poorly. Still you should buy what appeals to you, not to us here.
i got one more question. in american money we have pennies, nickels, dimes, quarter.What is the ancient greek denominations? thanks
It depended on the culture/city sir. "Greek" covers hundreds of cities that issued coins, and there were different coinage denominations and weight systems in effect. Bottom line, there were coin denominations, but many different systems, like comparing the US, Mexico, UK, China, and a few other countries. THey all have denominations, but are different systems.
While I agree with the medoraman answer, the most common and well known system was based on the drachm which often had a 4 drachm (tetradrachm) and half drachm (hemidrachm). For smaller change, there was the 1/6 drachm called the obol which also had fractions in various systems and sometimes multiples like the trihemiobol (3/2 obol = 1/4 drachm) or diobol (2 obols = 1/3 drachm). Various places that used the system made different coins from different metals (there are silver obols and bronze obols). This was one basic system but other places used other systems with names like stater or litra and, guess what, they had fractions and multiples as well. Now you know why medoraman gave a short answer. My answer above is less than half complete of fewer than half of the more common systems. A big mistake made by beginners is thinking of antiquity as some sort of consistent and organized unit. There is no answer to any question: "How did the ancients do it?" If you want to know how the ancient Athenians of the 5th century BC did it, we might answer but the Athenians a few years later and another city a few miles down the road did it differently.
Silverdrachm, I think you really need to learn more before you dive into collecting. There have been some great books mentioned on this forum - check them out!
If you know you want to specialize in Greek, I would suggest Greek Coins from the World of Numismatic series. You can get it on Ebay at times. Wayne Sayles has an Ancient Coin Collecting book Vol I for general and a Volume II for Greek. In 1978 Sear published Greek Coins and their Values. Its a two part series, the prices are out of date but shows you much what is available and relative rarity. Another good overall book is Head's Historia Numorum. It was published a century ago but still a great book. Or you can just go to a site like cngcoins.com and browse through their Greek, and also learn a lot about them at the same time. If you have any questions, just come here and ask. Chris