The stones for the ramp and the altar were brought from the valley of Beis Kerem. They dug into unworked soil in order to acquire whole stones that had never been raised with iron tools since iron would disqualify the stones just by touching them; the stones would also be disqualified if they were chipped by any material. If a stone got chipped, that one would be disqualified but the others would not. The stones of the altar were whitewashed twice a year, at Passover and Succos; those of the Sanctuary were whitewashed once annually. Rebbi says that the altar stones were washed with a cloth every Friday because of the blood. The whitewash was not applied using an iron trowel out of concern that it might touch the stones and disqualify them. The reason that iron has this effect is because iron is used to shorten lives while the altar is intended to extend lives. It’s not appropriate for something that shortens lives to be lifted on something that extends them.
There were rings north of the altar arranged in six rows of four, though some say four rows of six. The animals’ heads were placed through these rings when slaughtering them. The butcher area was north of the altar, where there were eight short pillars that had cedar blocks on them. Each of these blocks had three rows of iron hooks fixed in it, on which they would hang and skin the animals over the marble tables that were between the pillars.