Environmental impact of sharpening stones

[bosknurft]

I recently read a blurb on a website that, seemingly proudly, explained that to produce 1 kg of Belgian water stone, 1500 kg of rock need to be removed. I've heard other sources describe natural sharpening stones as 'increasingly rare' as well.

All things being equal, I'd prefer to use natural materials, but I don't particularly like the idea of contributing to a process that, to me, at least, sounds very destructive and wasteful.

On the other hand, I know even less about the production process for synthetic and ceramic stones. For all I know, the production processes involved in producing those make removing one and a half ton of rock seem relatively modest by comparison.

Is there anyone who can shed any light on this (or at least give some context as to how bad 'wasting' 1500kg of rock is in mining terms)?

 

[joejoe]

does not sound cost effective

 

[redneck]

I think if 1 and 1/2 metric tons of rock had to be moved to produce one stone then that would be reflected in the price, ie the stone would be outrageously priced, maybe cost hundreds of pounds..if it doesn't you can be pretty sure that the blurb is at best misleading and at worst a lie!

 

[silvergirl]

I think if 1 and 1/2 metric tons of rock had to be moved to produce one stone then that would be reflected in the price, ie the stone would be outrageously priced, maybe cost hundreds of pounds..if it doesn't you can be pretty sure that the blurb is at best misleading and at worst a lie!

Yea, but...

Rock is just there, no-body paid for it to get made, so you're initiall cost (in monetary terms) is nothing. You just have to say this land is mine .

OK you have to pay for processing, but that may not be that much really. And the waste is probably not 'wasted' as it will be used for other applications, gravel etc.

But there are issues around natural resources being use up faster than they are being made. Humans are now a hugh geological force on the planet, and that is saying something when you consider that the UK used to lie south of the equator.

 

[FGYT]

how big a block do you think 1.5 tonnes of rock is
its not that big
http://www.seed.slb.com/qa2/FAQView.cfm?ID=395

so a meter square and half a meter high

thats not massive bout 4 wheel barrows (volume not weight )

ATB

Duncan

 

[Minotaur]

Another reason to use the £5 pound sharpening kit!

It has to be more eco friendly than that.

 

[Tadpole]

We’re not talking your “average sharpening stone” here, you're talking about Coticule whetstone, (8000 grit there or there abouts) from Belgium, these stones run at about £70 for a 6”x 3” x ½” thin sliver. Some of them are so thin that they have to be backed with a stronger schist, to stop them from breaking.
The reason for the amount of over burden being shifted is the rock is in thin layers, most of which is no use, because of inclusions.
Belgian Blue Whetstone is found in the same kind of place, is much cheaper and ranges from 4000 grip to 6000 grit, and comes in thick enough layers not to be so wasteful.
And it’s not like the overburden is “wasted” as quite a lot would be sold as building material.

 

[bosknurft]

Yes, it was the blue whetstone I was interested in. And I suspected 1500 kg of rock wasn't particularly 'wasteful' in the grand scheme of things, I just lack the ability to see numbers like those in perspective.

Thanks a lot everyone!

 

[Tengu]

How long do these things last you anyway?

 

[IanM]

Very roughly as a general rule of thumb, if you take the price of something and calculate how much energy that would buy at your local, most expensive rate that will be the energy costs of producing that item. That then can be translated into Carbon Dioxide if you wish.

So, a £70 waterstone would translate into 705 kWh (I buy electricity at 9.93p/kiloWatthour) and this could also be measured at 303 kg of CO2 (@0.43 kg for each kWh)

Rough and ready but it puts it into context and for the real world won't be too far off. In general the intrinsic cost of what we buy is low but the cost of production is mostly energy at the end of the day.