Slag specimens

Slag is an industrial byproduct of various industries, including metal smelting and glass working.


Slag specimens

Slag is an industrial byproduct of various industries, including metal smelting and glass working. These slag specimens are sold for students and geology classes, etc - as study pieces. They are also ideal for reenactors living history displays, and museums of various kinds - especially museums dedicated to mining or metalwork.

We currently have two types in stock, a common black type found across much of the UK, and a more interesting blue glassy type found in Germany.

Black specimens: These pieces come from a range of locations, as slag is found all over the UK. It was widely used as hardcore for train track and road building, so is found in some really unlikely places!
Most of the pieces we sell actually come from my garden. I live alongside a road built between a city and a major colliery, within a few hundred meters of a railway line and canal - go figure!

Blue specimens: This is smelting slag from Germanys Harz mountains, and is hundreds of years old. It is likely to be copper smelting slag. A similar material is sometimes known as "Sieber Agate", after the Sieber river in the Harz mountains - however, it is not an Agate. This material is occasionally sold polished or tumbled. Expect blues, greens, greys, purples.


Frequently asked questions and delivery information

How do we grade stones?

There is no overall universal grading system for the majority of our products. As such, the grades we use are internal only. They simply refer to higher and lower qualities, but they may be entirely different grades to other websites. C grade pieces are of lower quality than B grade, which is lower than A grade.


How does our ordering and delivery process work?

You place an order via the website. When it’s been picked and packed, your order will be marked as completed and dropped off at our local post office. We have an account with the post office called a “Drop and Go” account, which allows the post office staff to process our parcels when they have free time, rather than me queuing up and delaying everyone else.

I get tracking information etc online when this has been completed. I typically do not send tracking information to customers unless they request it – but if you’ve requested tracked postage, it has been sent tracked! If you have any worries or concerns about your parcel being delayed please feel free to get in touch and I’ll send the tracking info over! We also get delivery confirmations for parcels over 25MM thick by default.


How do international orders work?

After Brexit, with the UK leaving the European Union, certain things have changed with regards to international orders. European Union customers will now likely be liable to pay the same amount of import VAT as any other international customers. You will be responsible for any customs and import fees.


I’d like to return my order for a refund.

No problem at all – just get in touch and we’ll arrange it. You can read our full returns policy here.


What payment methods do you accept?

I can accept Paypal, Stripe, cheque, and direct bank transfers. Paypal and Stripe will both allow you to pay with credit and debit cards.



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