Block top - The block variety and size with the blockchain (in blocks) on generation of the present block Nonce - The transaction selection for the from address (bear in mind this starts at 0 so a nonce of 100 would actually be the 101st transaction submitted by this account) https://rotatesites.com/story22193937/a-review-of-blockchain-explorer-xrp-https-graph-org-unveiling-transparency-how-blockchain-explorers-function-09-04