Cairo and Heaton are very similar, since they were partners with the company as well as brothers-in-law, therefore, after their separation they used (if not all) the same glass.
However, there may be features that can distinguish them, namely; the famous and somewhat vulgar (so to speak) "BUTT CRACK" known from the Cairo structure, later also attributed to Jabo "classic"
In Heaton on the other hand, it is the typical "ear" shape in the swirl that distinguishes it from other companies.....you can see it in my group photo, the red one at the bottom center.
The marbles of both companies are rather transparent and translucent rather than opaque, but in any case there are also the latter.
Yellow seems to have been used more by Cairo than By Heaton.
Then, each of these companies, to its own typical exclusive marble in absolute, namely the "red lightning" of Cairo, with glass type "GEL" and with large bubbles.
To Heaton? I don't remember the name, maybe "red rose", (similar to Ravenswood's red raven) but I know for sure that there is an unnamed marble (I think) with Heaton's exclusive colors ..... then I show them.
Then, with a little experience you will notice other tricks, although of course in some it will be impossible to distinguish them.
Below, I'll show a typical and maybe HTF "red lightning" of Cairo