I live in the Catoctin mountains in Maryland, which was historically a very big charcoal and iron producing region. 
hiking behind my house, I found this rock. To my knowledge there was no iron production on my property, but this piece of “rock” looks suspiciously like slag, which leads me to think iron used to be produced very near where my blacksmith shop is currently.

Looks like it could be. Perhaps they got tired of big piles of slag, ash, etc. at the bloomery and hauled it off a ways to dump. It might have fallen off the wagon too. You can use a compass to see if it effects the needle.

It might make an attractive fireplace or masonry forge, I like shiny black.

Frosty The Lucky.

I will test with a compass, Frosty. We are about 4 miles away from the Catoctin Iron Furnace, which was a fairly large iron producer during the Civil War. Despite being in the north, it 'employed' a large number of African American slaves, which is a sad mark on our hometown. But the iron furnace is still there - they have a festival every year that for the past two years I have demonstrated at. They do a live iron pour, which is really quite something. 

I doubt they would have carted the slag a full four miles, considering the iron furnace was downhill and there is a perfectly good valley to dump slag in. All surrounding us there are old sites where iron was produced even in the colonial era, I believe. We found an old wrought horse/mule shoe decades ago - the grain is clearly visible, and would make sense given the iron and charcoal. 

Here's the website for the foundation preserving the heritage of the Iron Furnace:

https://catoctinfurnace.org/

Really cool piece of history, although I'm biased for living next to it. 

Almost certainly slag.  The vesicles (bubbles), the shiney black surface, and the sharp edges on the face nearest the camera indicate a high silica (glassy) slag.  Slag was used for a lot of things including fill for canal and railroad embankments but often only when transportation costs made it cheap because it was inferior to natural rock or gravel.  It was lower quality because it was more brittle in use and would break up more easily than natural rock and was also lighter in weight which meant the fill could shift more easily.

Like Frosty says, it could have just fallen off a wagon.

"By hammer and hand all arts do stand."

Because Maryland was not in rebellion slavery in that state was unaffected by the Emancipation Proclamation.  Slavery in Maryland was abolished by a new state Constitution effective November 1, 1864.  Surprisingly enough Delaware was also a slave state in the 1860s.

Maryland had 87,189 slaves in the 1860 census, about 12.6% of the total population.  Here is a link that gives the breakdown by county:  http://slavery.msa.maryland.gov/html/research/census1860.html

Interestingly enough, the Black population of Maryland in 2020 was about the same percentage as slaves in 1860.

GNM

ANOTHER place for the bucket list! I want to see Sturbridge too, guess we'll be close enough to see both and whatever's in between. 

Frosty The Lucky.

1 hour ago, Frosty said:

ANOTHER place for the bucket list! I want to see Sturbridge too, guess we'll be close enough to see both and whatever's in between. 

Frosty The Lucky.

When you make it down this way, stop by! The Mrs and I have plenty of space!

 

George, thanks for that information. I wasn’t aware of the reasons behind the legality of slavery in union states.

The Slag may have been used as road fill- there is an old path that leads over the mountain from a failed ski resort construction project….

When we start snow birding in the RV I'm sure we'll both keep our online friends up on where we're going. I'll be checking IFI when we're near wifi and I'll be my usual talky self so suppose everybody on the planet will know about where we are headed. 

All we'd need is room to park a small RV and we're golden. 

Frosty The Lucky.

Most of the slave states that did not secede (Missouri, Kentucky, Maryland, and Delaware) abolished slavery on their own before the adoption of the 14th Amendment.  They saw which way the wind was blowing and although initially the Civil War was mainly about reuniting the Union it gradually became a federal war aim to abolish slavery.  Techically, the Emancipation Proclamation only freed those slaves which were in areas controlled by the Confederacy as of January 1, 1863.  Legally, it did not affect the states that did not secede or those areas of the Confederate States which were under Union control as of that date.  In actual practice, slavery pretty much became a dead letter any where Union Armies had control at that time, e.g. much of Tennessee, southern Louisiana, coastal enclaves along the Atlantic coast, and parts of northern Virginia.  As the Union 

GNM

15 hours ago, Frosty said:

ANOTHER place for the bucket list! I want to see Sturbridge too

While you're at it, check out the Hopewell Furnace National Historical Site: https://www.nps.gov/hofu/index.htm.

They've also got a pretty well kitted out blacksmith shop.

That’s not too far away from Longwood Gardens- there’s some nice blacksmithing work in the park, as well as some incredible gardens

I enjoyed the Hagley (especially the old powder mill) when I was up that way years ago.

Sure looks like slag of some type. Are you near a current railroad? You also tend to find thermite slag where they weld rail in, and it looks, well, a lot like that. I used to bring bits of it home from work once in awhile.

There was a 19th century blacksmith shop on my family’s property and I have found exactly what you have around the site

Looks nothing like the 'late model" slag.  My driveway is paved with slag from the steel mill in Cartersville. Lot cheaper than gravel, (slag is free to haul off, and just have to pay for the transport) and packs in very well. 

Bluerooster, 

Sorry - just now seeing that I had replies I never replied to. We ended up getting our property assessed by the forestry department for a management plan, and LIDAR mapping revealed extensive (old) trail systems from the turn of the century and prior. Our property was logged for charcoal production, which likely happened on site. The road in question where that slag was found was an old (circa 1800s) road originally used by the founders of Mt. St. Mary's College to quarry stone for their buildings. The Catoctin Iron Furnace, which was the recipient of the charcoal, is only about 6 miles away, so I imagine there may have been some exchange of goods. I suppose the slag could be from charcoal, too, but I find it a bit less likely. 

The history of the mountain is a bit sparse; it was good to know that our mountain holds some economic possibility, if anyone wants me to start making them charcoal! haha. 

I hope it's not rude for me to chime in.  You all seem very familiar with slag from older production methods.  Could anyone tell me more about this piece?  I found it in the Dog River in Montpelier, Vermont.  I haven't been able to find any other examples of slag with this sort of conglomerate, granular interior and I'm curious what it's from.

Good Morning,

It's a Rock, Not stuck between a Hard Place!!  LOL

Neil