Concave Diamonds #557, Northwood
The pattern is a soft quilting or diamond effect, always with a stretch-type iridescence. Complete water sets, like the celeste blue example at left, will include coasters for the tumblers and a lid for the pitcher. Found mostly in celeste with occasional vaseline and rare russett/olive pieces showing up.

Hartung Book Five: Concave Diamonds
Hartung Book Nine: Concave Diamonds Open Sugar

Water set, 14-16 pieces (with coasters, lid)

Celeste blue, 140 (2017),
   300, 475 (both 2019), 225, 400 (both 2020)

Celeste blue, with original Jewel T box, 550 (2008)

Water set, 10 pieces (4 tumblers, coasters, lid)

Celeste blue, 375 (2013)

Water set, 7 pieces (no lid, 6 coasters)

Celeste blue, 225 (2019)

Water sets, 7 pieces (with lid, no coasters)

Celeste blue, 300 (2016), 226 (2018)

Water sets, 7 pieces (no coasters or lid)

Celeste blue, 100-200

Vaseline, 1,300 (2000), 800 (2006),
   700 (2007)

Water set, 8 pieces (6 tumblers, lid)

Celeste blue, 160 (2014), 150 (2016),
   110 (2017)

Water pitchers

Celeste blue, with lid, 300 (2018), 90 (2021)

Celeste blue, 2 tumblers, lid, 70 (2017)

Vaseline, 800 (2008)

Water Tumblers

Celeste blue, 15 (2019), 10, 15 (both 2021),
   10 (2022)

Ice blue, 2 sold for $30 each (2022)

Olive/russet, 450 (2002), 450 (2012),
   400 (2019)

Topaz, 55 (2020)

Vaseline, 30, 50, 65 (all 2019),
   75, 80 (both 2020), 30 (2021), 80 (2022)

Tumbler and coster

Celeste blue, 5 tumblers, 4 coasters, 50 (2019)

Vaseline, 60 (2013)

Tumble up (water jar and small tumbler that stores inside neck), sometimes called a guest set

Blue, 175 (2009)

Celeste blue, 200 (1997), 525 (2000)

Olive/russet, 155 (2004), 100 (2009),
   250 (2019)

Vaseline, 1,050 (2016), 375 (2017),
   325 (2019)

Tumble up tumblers only

Blue opaque, 80 (1998)

Celeste, 20 (2011), 35 (2015), 55 (2019)

Olive/russet, 13 (2011), 50 (2012), 15 (2019)

Sapphire blue, 20, 35 (both 2011)

Vaseline, 50 (2012), 65 (2017), 35 (2019)

The 6-inch ruffled vases were whimsied from the tumble up bottle minus the handle.

Vases, about 6 inches tall

Celeste blue, 75 (2014), 60 (2015), 60 (2017)

Citrine, 65 (2005)

Ice blue, 45 (2007)

Russet/olive, 85 (2004), 130 (2007), 60 (2015)

Vaseline, 450 (2003), 85 (2016), 550 (2017)

Updated 11/24/2022

 It's not known if this pickle castor was made by Northwood or is from the same line, but, in marigold, it sold as Concave Diamonds at a 2009 auction for $545. Another brought $375 in 2012.