McCoy #739 Interlocking Jardiniere

This is a McCoy Interlocking Jardiniere from the early 1950s. In the old catalogs this is listed as item #739, and was only available in yellow or green (supposedly), but as you can see this one is clearly gray, which was previously undiscovered by the McCoy community. I found it on Facebook marketplace. It is still available on there. Just look up McCoy pottery and type Los Angeles as the location and you'll find it.

Anyway, these originally came with an unglazed white liner pot inside, and as it's named, the pieces Interlock with each other like a puzzle.

A very similar Jardiniere was also featured in catalogs that were not interlocking, and have a square opening instead of a round one. It's listed as #39, also available in yellow or green, and can also be found in white. Both have a McCoy USA type 1 mark and #739 is very hard to find with the original liner pot.

Rarity on both: 9.1 very common
Gray example shown: 1.5 Extremely rare

Update: It has been confirmed by the McCoy community that this is a non-production color. Value cannot be determined because these never appear on eBay in Gray. It is speculated that this color may have been for a contract order. No approximate number produced is known.