[Tagging] quarries in engineering

[M∡rtin Koppenhoefer]

2010/11/5 Richard Welty <rwelty at averillpark.net>:
> On 11/5/10 11:05 AM, Richard Mann wrote:
>>
>> Gravel/sand/clay come from river beds, generally. Quarries are when
>> you blast half a hill away.
>>
>> But I'm not an engineer...
>
> gravel around here comes from excavating in the sides of hills
> that are actually piles of debris left by glaciers in a previous ice
> age.
>
> in the southeast US, clay comes from pretty much anywhere you
> use a shovel.

thanks for all your comments so far.

could a clay pit that is used only to excavate clay be put under
quarry, or would that be missleading? I know that these are all
open-cast mines, but the wikipedia entry for quarry seems somehow not
precise enough when it comes to delimiting the usage.

cheers,
Martin