I've wondered why crushed glass isn't used along with asphalt to #1 get rid of a lot of glass and #2 maybe get longer were out of our roads. I'm not saying this is what you have, It just reminds me of what asphalt/glass might look like.
They make glassphalt, also spelled glasphalt, but a lot of factors come into play regarding its use. Here are some I found on the pothole info website.
"So why is glassphalt not used routinely in road building? There are several problems:
Variable rock economics. At the most, the glass content would comprise between 10 and 20 percent of the pavement. So standard asphalt-making equipment and procedures would always be used, but this would reduce the costs from aggregate (crushed rock) that makes up the bulk of asphalt. Aggregate pricing varies from location to location, a function of raw sourcing and the distance required for transport. So in some areas, glass provides a cost-effective dilution, but in other areas not.
Municipal variables (recycling and asphalt manufacture). According to the Glassphalt Paving Handbook (Asphalt Institute Manual Series No. 4, 1989, University of Missouri-Rolla), “The best possibility for sustained production of glassphalt is in communities with municipal asphalt plants, because the community can make a direct correlation between the extra costs incurred in glassphalt installation and the savings from diverted solid waste tip fees.” The handbook goes on to say this is not the case in most of the U.S.
Not a simple substitution. The Glassphalt Paving Handbook also makes a point of how you cannot simply feed broken or crushed glass into the aggregate. After collecting the glass (by whichever method the municipality uses), it needs to be processed to a specific size (aggregate), after which batch modifiers must be altered along with the asphalt manufacturing operation.
Limited applications. While the presence of glass in the pavement presents no danger to humans or damage to vehicle tires, the skid resistance of glassphalt pavement is slightly less than that of standard asphalt. This then limits its use to lower-speed roadways – and prevents it from being used to build 65 mph highways."
Also, I'm not suggesting the object in question is glasphalt. I was just responding to hvacker's query.