I would suggest one of two methods:
Compact the material into a CBR mold with its moisture content at around 10 to 11 percent by weight. Soak the material,in the mold, for at least 24 hours, then carefully extract from the mold as a cylindrical specimen and allow to dry. Run an unconfined compressive strength test on the material to determine its compressive strength. Compare to similar, non-cementing materials.
The second method is similar except you will simply place the material into a 6" diameter by 12" tall compressive strength test mold and moderately compact it in 3 lifts. We the material and allow to soak for at least 24 hours. Pour off all water, allow to air dry and then test in unconfined compression. Compare to other similar, but non-cementing materials.
If in either case your unconfined compressive strength exceeds about 200 psi, you are getting some significant cementation.
Good luck.