They don't look to be very old due to the lack of corrosion.
So depending on how deep they were buried and the location you found them in, they may be votive offerings.
Dave
"A votive offering or votive deposit is one or more objects displayed or deposited, without the intention of recovery or use, in a sacred place for religious purposes. ... The modern construction practice called topping out can be considered as an example of a votive practice that has very ancient roots. Some offerings have apparently been made in anticipation of the achievement of a particular wish, but in Western cultures from which documentary evidence survives it has been more typical to wait until the wish has been fulfilled before making the offering, for which the more specific term ex-voto may be used. Other offerings were very likely regarded just as gifts to the deity, not linked to any particular need."