A cache is a term associated with a dedicated amount of intentionally-buried mass or object. Some examples might be old Uncle Frank's hidden (a cache) jars or coins because he didn't trust banks during the depression era, of during early settlement times any bank was quite a ways away, if there was one.
I know of a hidden Piggy Bank that a gal and her friends intentionally buried as young kids. Too many early westerns on TV and theaters got them to plan this act to hide a container of money that they imagined was part of a stage robbery. Their 'plan' was to dig it up later in the year, but they forgot the specific location. This qualifies as a 'cache' because it was a group of coins, in a container, buried with the intent to hide it for future recovery.
There was a bank robbery in Eastern Idaho in April of 1916. Shooting also occurred before the two bank robbers rode off on horseback. With money, and I believe it might have been $4,000 or $14,000 and possible all gold coins fro some of what I have tracked down, was in at least one saddle bag. As they rode southwest they feared being caught with the loot. They stopped at an old homestead in the lava rock area and buried ('cached') their saddle bag/s, thought about hanging out there for the nigh but feared the old guy would return soon. Like many robbers of that era, their unlawful take would be 'cached' for a certain period of time and they would return when things 'cooled off.' Things did 'cool off' the next morning when they rode into an ambush by a posse which left them both cold. Dead. Without the bank loot and no longer able to tell what they did with it.
When my grandfather lived in northern Mexico and Pancho Villa was on his raiding missions, many Mexicans would gather their valuable gold and silver jewelry and other prized candle sticks and other goods and bury them . Certainly, these decision were to keep from having valuable in site, and the hidden items could be dug up at a future safe time. To intentionally hide these in a dedicated container is also a 'cache'.
Jumping off swings, rolling on the lawns in playful wrestling, sliding into base during a baseball game or meeting you match when being tackled when playing football can cause the loss of a single coin, a couple of coins, a pocket knife, or a 'spill' of several pocket items. These are simply accidental 'spills' and not a 'cache.'
Not meant to dampen your story of your finds, but there is a difference. Like others have wondered, I am also curious why you discovered one 5