Is this black glass with pontil mark?

I am new to this site and to digging bottles. I have been digging in a trash pit that has given me bottles from 1890-1920 period. Then I found this broken bottle (attached). I don’t have a lot of experience, since I am new to collecting and digging bottles, but this looks to me like black glass (from everything I’ve read and seen on different sites). When I look at it, it looks like it’s black. When I hold it up to the light (looking through one layer of glass) it appears to be dark green. The bottom is 2 ½ inch diameter. With my little experience, it looks like it has a pontil mark, and is sunk in at least an inch. The rounded bottom edge is not perfectly round. The bottle doesn’t appear to have any seams running up the side. My question is, is this black glass? Is that a pontil mark? What date period is this from? I understand that someone could have had an old bottle back in the early 1900’s, and it finally got thrown in the dump. This dump was along a fenceline of a house that is no longer standing, and the dump was only about 10 x 10 ft area. All the bottles were found from the surface to 5 inches down. Below that was just regular colored dirt. I found about 30 unbroken bottles, and identified about 20 or more broken bottles. There was tons of fragments in this area. But they all seemed from the same period.

Any help anyone could give me on dating this would be great. I know this is broken, but if this bottle is much earlier, I want to be sure to pay closer attention to this site.

Here's another pic.

Hello

It's a sand pontil, which was in use up to the early 1870s,, & yes it is ''blackglass''.

Dave

Hello again;

Re my last post; I should have said the sand pontil was MADE up to the early 1870s. Bottles were often re-used, & could have been in use at a later period.

Dave

Nice find, broken or not....now if I were you, and assuming you don't own a probe, I would go to Menards (they have a nearly 3' screwdriver for under $10, get a flat head, not a phillips) or any other large hardware store and buy a long size screw driver to use and go back and probe under that regular looking dirt. With little experience, you will soon discover how to tell where the bottles are. You sound like you are digging in a typical area where privies are found, at the back yard property line, and some were as big as you describe. If a temp. probe is not an option, I would suggest digging an exploratory hole, usually 3-4 feet deep to see if either the ground changes color or you actually break through to a use layer with glass. Dig where you found the most glass. You might need to dig a few in an area that large, but it should pay off. Sounds too shallow to just end, privy, dump, or whatever. Could be a filled in ravine, so being thorough may pay off. Also, you might just come accross a fragment or two, and sometimes not nearly as old as you hope for or want. Don't get discouraged, as privies often have "caps" of occasional bottles and trash until you break through to the actual use layer. These caps can range in bottles from the last period the privy was used to when it sank down and was filled whenever with whatever. Sometimes you may find a "late toss" like your pontiled base. Often times as mentioned in a previous post, these are bottles reused for purposes other than their original intent. Most common are bottles reused for bluing, an early type of bleach for washing, and they preferred larger bottles for some reason for this reuse. Often have a tell-tale residue of the old bluing, sometimes as much to make the bottle look like it is cobalt blue until it gets cleaned! I would suggest getting a good probe as they are invaluable in the hunt. Google oldwestbottles for the best state of the art probes, and get digging and have fun! Jack

PS- Also, when an old house gets knocked down, often demo crews have zero interest or time to be messing with bottles. Sometimes they scrape open the edge or top of an old privy and scatter them over the lot. That's when it can get tricky, but with good detective work, looking for a greyish colored soil or a rust colored soil, one can often backtrack the debris field to its origin. Whole bottles are a good sign for sure, and where I would start. Sometimes the crews also try to rebury the glass, often where it originally comes from, rather than creating a mess of broken shards. Hope this helps.

Thanks for the information Canada.

Jack,

Thanks for the information and insight. This trash pit was on a level piece of ground in the woods, just on the other side of the fence from the corner of the property. This area was a couple hundred yards from where the house was standing. On the inside side of the fence (across from my trash area) was a bigger, newer trash pit. Nothing too old in that area from what I could tell. Did they use to throw dirt on top of trash areas, and then throw more garbage on top? I do have a probe and I will probe this area. Thanks again.

I was going to mention the possibility of being a country dump site, which is what it sounds like now. Too far from the house to be a privy, unless there was an older house on the property closer to the site. And usually country cousins threw stuff away as you describe, rather than filling a privy unnecessarily. Why fill in a hole only to have to dig another one that much sooner, than fill in that ravine in the back? Unless they wanted it to stay hidden forever, ie: the missing vase, (broken while horseplaying,) the booze bottles she didn't approve of, the std medicine bottles, etc.

Is it possible that there may be another layer underneath the dirt that was underneath the bottle layer that I was digging in? Did they cover up country dumps with dirt, and then throw more garbage on top? Thanks for the help. I will be back to cthe sit to check into it more closely.