How much should I pay for a summon skeleton gem?

Title says it all. I'm pretty new, so information on current currency exchange rates/common abbreviations of currency would also be helpful.

Thanks!

most gems are far too common; 1 fuse or 1 alc usually. more popular gems like multistrike, enhance, empower will fetch ~2 chaos depending on how much the person selling thinks it is. honestly, if you have a list of gems you need, there are lots of super friendly people on these forumns who will help you out with gems BUT also help with some gear.

a good way to find prices on things is using poe.xyz (site database of this site) you add your query and it will search the forums for related posts and prices if added.

Following is approximate rates:

2 fuse=1 chaos
30 chaos=1 ex
12 regrets=1 ex
10 GCP=1 ex
divine=1ex
eternal=3.5-4ex

all the other little currencies stagger so these are MY prices
10 chromes=1 chaos
20 alts=1chaos
10 jewelers=1chaos
80 chance=1 ex
90 alc=1ex
45 chisels=1ex

these prices fluctuate everyday and by every seller so its best to just watch trade chat until you see someone offering something you can afford or just ask them