A topic from AEG's L5R CCG Rules forum, copied for Oracle of the Void from a copy of the forum saved in October 2015, so pages it didn't save are missing. Players' names are left out; the rules officials are named. Rulings are as they stood on these dates; later rulings, the rulebooks and the Rules Archive may differ.
Is the +1F on Stones of Purity a numeral (as mentioned in Alchemy Lab)? If not, what is a numeral, according to the L5R rules framework? There is no definition in the comprehensive rules.
Relevant text:
Stones of Purity: "After you Equip this Spell, give this Shugenja a number of +1F Rock tokens equal to his Chi."
Alchemy Lab: "Open, w: Increase a positive numeral on your target Spell by 1."
Is the +1F on Stones of Purity a numeral (as mentioned in Alchemy Lab)?
Yes, it is.
However, I should mention, targeting Stones of Purity with Alchemy Lab and choosing to increase that +1F to +2F will not change the value of tokens it already gave out when it was Equipped (before it became a legal target for Alchemy Lab's Open ability).