Apologies if I offended anyone. I guess I just see it as funny, that so much importance is placed on whether this pill is the same as that pill. As long as a tablet contains a medium to large dose of MDMA, and nothing else toxic, who cares?
It's mostly guess work, but I suppose there are some ways in which 2 pills might be evaluated outside of a forensics lab. These ideas might work, but there's countless variables to consider, some of which I possibly haven't so all criticism please.
OK, first you might try to discover whether the pills have been made in the same press. It's not always as easy as it might sound, particularly when the pill was obviously produced in huge quantities, perhaps even using several presses working simultaneously. If you think 2 tablets have just got the same ingredients, then you can still examine them this way.
Get a magnifying glass or better still a microscope. If the tablets have been pressed in the same press, but with different stamping rods, you should still be able to identify similar markings on the sides of the pill. These will be from the walls of the pill well. Commercial pill machines will produce better results and so it may be hard to notice the imperfections present on those home made by drilling out a stainless steel well body.
If large batches were produced by a "homemade" press, then it would be a multi press having several "well holes" which are filled with powder mixture before being pressed. Each of these wells will have different characteristic markings, so if a press contained a hundred wells it would require looking through large batches to find and list all the different kinds. However most home made presses IMO are likely to be around 50 max due to factors such as load distribution of the press and therefore the size of the unit.
So, if comparing large batches of tablets and remembering or recording images seems too much work, but you suspect the ingredients/ binders etc are the same, then try first coarsely crushing a portion of each tablet, passing through a mesh filter, and using a microscope/ magnifier to examine the larger and smaller pieces for any similarity.
If you were deadset keen, you might also try this.
Weigh each tablet before powdering in a mortar and pestle. Freebase each separately and keep both the amine and the filtrate. Weigh the recovered amine from each pill. This accounts for differences in MDMA or other amine content. The residues and amine weights should add up to their respective pill weights allowing for a bit of loss.
Then dissolve each of the remaining residues in alcohol. Filter what remains and weigh each filtrate. If the tablet mixtures were identical, and allowing for differences in amine content, what doesn't dissolve should be close to identical in weight if the mixtures were the same, bar colouring. You would want to do the experiment 3 times and average the results (more if any result is more than 1-2% out from the other 2 figures of the same material) If nothing dissolves, try first warming the alcohol.
Of course with any such operation you will need an accurate and precise balance, and be meticulous with your handling and weighing. Error of equipment should also be factored in to calculations. Using more of each tablet, say 3 of each will make things easier.
Std warning applies: it could look like manufacture, do it at your own - fully informed - risk
That's about as close as you can get to any certainty. But what it comes down to, is what actives are in each. For this you'll need analysis equipment unless your solubility and chromatography skills are exemplary.
