Thread: Hindostan Hone?

It certainly has the thick and thin layered banding that you associate with these stones, and the colour is about right. They seem to be greyish/yellow/tan most often with orange/brown splotches and stains, but how much of the staining is due to them having been used with oil and having metal scrapings oxidising on them is debatable. They are sometimes called orange stone, not because of the colour (a forgivable mistake to make) but because of where the vast majority of them came from Orange County.

I suspect the colour of the surface could depend on the colour of the banding - if the surface was smoothed off along a darker banding then obviously the stone would be darker than one smoothed off along a lighter banding. The banding arose due to the stones components being laid down in silty water, the degree of particle deposition being influenced by the tides. It is not unusual to see a thick and thin band side by side, echoing the rise and fall of the tide. During mining operations it was said that the rock could be split very exactly along these lines, so there was a minimum of waste.

Here are some pics of a few of the stones in question:





It appears that another outcrop was found on an island in a lake between Vermont, USA and Quebec, Canada. A lot of that discolouration is obviously due to staining. Although a large proportion of the stone went into making oilstones, a larger percentage was used to make tombstones. These have weathered and discoloured too, but still show quite a range of colours from orange/brown through yellow, grey, cream tan and off-white. The darker brownish/orange discolouration appears to be some sort of rust stain, so some traces of iron oxide must be present in the rock.

Regards,
Neil