My holed ancient coins page gives an overview of different types of holed coins. These are my holed coin galleries:

Hellenic Coins — Roman Republican and Augustan Coins — First Century Roman Coins — Second Century Roman Coins (this page) — Third Century Roman Coins — Fourth Century Roman Coins — Fifth Century Roman Coins — Byzantine or Romaion Coins of Later Centuries — Other Holed Coins of Varying Origins and Times

	Silver denarius of Trajan, 108 CE. 18 x 19mm, 2.96 grammes.	This denarius has a reverse showing fortuna, in this case meaning a wish for a safe return from a sea voyage. It has been carefully pierced so that both the emperor's bust and the lucky reverse are undamaged and can be displayed at will.
	Silver tetradrachm of Trajan, 114 CE. 22 x 23mm, 14.22 grammes.	This chunky silver tetradrachm is a good 3 millimetres thick, and would have made a weighty pendant. The piercing avoids both portraits, but has been made from the Trajan side, so may have been meant to honour the emperor rather than the local deity whose bust is on the reverse.
	Silver denarius of Hadrian, 128 CE. 16 x 18mm across, 2.86 grammes.	What could have been the reason for the three holes in this silver denarius? They were made front to back, leaving the emperor's head intact and displayed. Perhaps it was part of a mesh of coins linked together, part of a necklace or other ornate item.
	Copper as of Hadrian, 129 CE. 27mm across, 11.59 grammes.	This as has been pierced to show the triumphant figure of the emperor on horseback, holding his lance at rest. It shows considerable wear, so is likely to have been someone's favourite pendant.
	Silver denarius of Hadrian, 136 CE. 17 by 18mm across, 2.9 grammes.	This is quite a pleasant denarius of Hadrian, with plenty of detail, and attractively toned. Unfortunately the hole does rather get in the way of enjoying this coin to the full – it has neatly removed the head of Italia on the reverse.
	Copper as of Antoninus Pius, 148-9 CE. 27mm across, 10.7 grammes.	This coin was minted for the 900th anniversary of Rome, and celebrated the munificence of the Emperor, the games he gave and the gifts he distributed to the people. The hole was bored from the head side, which suggests that Antoninus Pius, rather than the elephant, was the important feature for its owner.
	Bronze AE27 of Marcus Aurelius from Amphipolis in Macedon, 161-180 CE. 27mm across, 11.8 grammes.	This coin has a large, crude hole without any interior wear such as might be caused by a hanging loop, yet it has been pierced in a position which carefully avoids damage to both the bust and the reverse design. So, perhaps it was just not used as decoration for very long. It does have a very expressive portrait of Marcus Aurelius, better than most coins of this type.
	Holed silver denarius of Lucilla, 164 CE. 18mm across, 2.79 grammes.	This denarius commemorated the marriage of Lucilla to Marcus Aurelius. It was most likely holed as a keepsake of a glamorous royal wedding. The combination of a portrait of the lucky princess, now raised to the status of Augusta and named on this coin as the daughter of Antoninus Pius, and the vows on the reverse, must have been irresistible.
	Brass sestertius of Marcus Aurelius, 175 CE. 30mm across, 26.7 grammes.	A large and heavy coin from Rome, this one carefully pierced so as to show off the bust of this popular emperor. Although there is old patina inside the hole, there is recent damage around it, perhaps caused by someone wrenching off a metal loop when it was found. That's a pity. I would have preferred to see a loop still in place.
	Copper dupondius of Crispina, 180-182 CE. 26mm, 15.3 grammes.	This isn't a rare coin, but I was quite pleased to pick up an example really cheaply because of the hole .. actually, in this case I don't think the coin would be particularly attractive even without the hole, but it gives me an instance of a hairstyle I don't have elswehere.
	Silver denarius of Septimius Severus, 194 CE. 16mm across, 2.2 grammes.	This is a denarius from the very start of Septimius' reign. The reverse design is a crescent moon and seven stars. The hole has been placed so that the coin can be hung around the neck with the moon and stars displayed. The design has an astrological significance, and this must have been a luck piece. The pattern of wear shows that it has been fingered a great deal, by a right-handed person, probably for years. This coin was struck at the eastern mint usually referred to as Emesa, where the pattern of religious belief differed from the centre of the Roman Empire.

Hellenic Coins — Roman Republican and Augustan Coins — First Century Roman Coins — Second Century Roman Coins (this page) — Third Century Roman Coins — Fourth Century Roman Coins — Fifth Century Roman Coins — Byzantine or Romaion Coins of Later Centuries — Other Holed Coins of Varying Origins and Times