Inverted Feather, Cambridge
Inverted Feather has a row of hobstars above columns of an vertical feather motif. There are quite a few shapes known, but only the cracker jar and parfait are seen with any frequency. There is one known marigold milk pitcher and a couple of marigold water pitchers. Some pieces are signed Near Cut.

Article on Inverted Feather

Hartung Book Three: Inverted Feather

Cracker jars

Amethyst base, green top, 2-3 known,
   175 (1998)

Green, 35, 40, 45, 65, 70, 100 (all 2018),
   35, 45, 95 (all 2019), 25, 35, 40 (all 2020)

Punch sets

Green, 7 piece, 950 (2009)

Marigold, 8 piece, 4,000 (1995), 1,400 (1997)

Marigold, 7 piece, 3,100 (2008), 650 (2009)

Punch base only

Green, 100 (2011)

Punch cups

Green, 60 (2005), 90 (2011), 35 (2013)

Marigold, 115 (1999), 150 (2020)

Table set pieces rarely sell, so it is difficult to establish value. Any, however would bear a premium price. The above amethyst creamer, with a rough lip, sold in 1998 for $100. The common parfait above, also referred to as a compote, is known only in marigold.
Table set, 4 piece

Amethyst, 1,000 (2010), 425 (some chips, 2012)

Butter dish

Marigold, 1,300 (2019)

Covered sugar, creamer, spooner

Marigold, 200 (2012)

Creamer

Amethyst, 95 (2004), 85 (2009), 245 (2015)

Marigold, 105 (2001), 135 (2016), 125 (2019)

Spooner

Amethyst, 175 (2004), 235 (2015), 175 (2019)

Sugar

Amethyst, 725 (1997), 535 (2015)

Parfait or small compote

Marigold, 20 (2018), 10 (2019), 15 (2021)

Large compote (9 1/2 inch diameter)

Purple, 200 (2013)

Wine glass

Marigold, 320 (2013), 325 (2014),
   280 (2020)

Cordial

Marigold, 500 (1998), 325 (2017)

Pitchers and tumblers in the Inverted Feather pattern are extremely rare. The pitcher above is courtesy of Ruth Phillips. John Britt reported six tumblers in marigold and a few more than that in green. Amethyst tumblers are also rare.
Pitcher, tankard style

Amethyst, 17,000 (2008)

Marigold, 4,250 (2010)

Marigold, minor chip on handle,
   1,300 (2014), 1,000 (2020)
Tumblers

Amethyst, 65 (2009), 325 (2010),
   525 (2020)

Green, 85, 160 (both 2019),
   140, 175 (both 2020)

Marigold, 450 (2010), 275 (2019)
As rare as most pieces in this pattern are, these two are even more so. The green bonbon, whimsied from the base of the cracker jar, sold in 1996 for $2,750. One with a base chip brought $450 in 2004. Another brought $700 in 2007 and $300 in 2013. In 2017 another green example sold for $725.

The vase, which appears to have been made from the pitcher, is courtesy of Don and Becky Hamlet, and sold in 2013 for $525. Another, or perhaps this same one, sold in 2020 for $750.

This Inverted Feather marigold spittoon whimsey sold at the Cristina Katsikas auction in 2020. It brought $2,900. Photo courtesy Wroda Auctions.

Updated 6/23/2021

This excellent photo of a beautiful Inverted Feather butter dish in marigold was sent to me by Sandy and Bob Sage. They got it at the 2019 Tampa Bay club auction. So far the only one known. Thanks guys.