A keystone is the wedge-shaped stone at the apex of a masonry arch or round-shaped one at the apex of a vault. In both cases it is the final piece placed during construction and locks all the stones into position, allowing the arch or vault to bear weight. In arches and vaults keystones are enlarged beyond the structural requirements and decorated. A variant in domes and crowning vaults is a lantern. Keystones, as a hallmark of strength or good architecture, or their suggested form are sometimes placed in the centre of the flat top of doors and windows for decorative effect, so as to form an upward projection of a lintel. Although a masonry arch or vault cannot be self-supporting until the keystone is placed, the keystone experiences the least stress of any of the voussoirs, due to its position at the apex. Old keystones can decay due to a condition known as bald arch. In a rib-vaulted ceiling, keystones mark the intersections of any two or more arched ribs. For aesthetics, keystones are larger than ribs in vaults and many of the voussoirs in arches, or embellished with a boss.

Mannerist architects of the 16th century designed arches with enlarged and dropped keystones, as in the "church house" entrance portal at Colditz Castle. Numerous examples are found in the work of Sebastiano Serlio, a 16th-century Italian Mannerist architect. Architectural sculpture Coping List of classical architecture terms Oculus compression ring Media related to keystones at Wikimedia Commons

The cuneiform i sign is a common use vowel sign. It can be found in many languages, examples being the Akkadian language of the Epic of Gilgamesh and the mid 14th-century BC Amarna letters. In the Epic of Gilgamesh it has a minor usage as a sumerogram, I; the usage numbers from the Epic are as follows: i-, I-. As i and one of the four vowels in Akkadian, scribes can use one sign to substitute one vowel for another. In the Amarna letters, the segue adverb "now", or "now, at this time", Akkadian language'enūma', is spelled with the'e'. In both the Amarna letters and the Epic of Gilgamesh another common use of the "i" sign is for the preposition, Akkadian language ina, spelled i-na, for in, for, etc.. Moran, William L. 1987, 1992. The Amarna Letters. Johns Hopkins University Press, 1987, 1992. 393 pages. Parpola, 197l; the Standard Babylonian Epic of Gilgamesh, Simo, Neo-Assyrian Text Corpus Project, c 1997, Tablet I thru Tablet XII, Index of Names, Sign List, Glossary-, 165 pages

Rudolph Foods is a Lima, Ohio-based producer of snack food, in particular pork rinds and cracklins. The company has six facilities in the United States and three international ventures. In addition to Rudolph Foods' primary business of traditional pork rinds and cracklins, Rudolph Foods manufactures non-pork rind snacks including Rudolph's-brand Cinnamon Churros, Original OnYums and Chile Limon Chicharinas, its family of brands include Rudolph's, Southern Recipe, Pepe's El Original, Gaslamp Popcorn and Lee's Pig Skins. Southern Recipe manufactures Southern-inspired snacks including pork cracklins. Southern Recipe makes pork rinds in various flavors including. Cracklin varieties include Traditional, Strips, Dipper Cracklins and Red Pepper Dipper Cracklins. Southern Recipe pork rinds, as part of the salty snack category, have seen a significant increase in sales and popularity as a result of listening to consumer feedback and offering new products that deliver desired flavor profiles. Pork rinds are considered to be a low carb diet snack – with zero carbohydrates and contain more protein than peanuts.

Pepe's El Original is an authentic Mexican food and snacks brand in the U. S. is produced by Inc.. Pepe's El Original first began production in San Antonio, Texas; the Hispanic brand maintains its heritage and dedication to authentic Pepe's snacks with a line of chicharrones, gigante cracklins, tender curls and dippers. Additionally, the Hispanic snack line offers other, non-pork rind Hispanic-inspired snacks including sweet and sugar Churros and chile limon Duros. Pepe's El Original pork rinds have seen an increase in sales and popularity as a result of consumer feedback and new products; the brand's chicharrones product line address the industry's growing Hispanic food trend, address consumer interest in “healthy munchies” and low carb diet snacks – pork rinds contain zero carbohydrates and contain more protein than peanuts. Lee's Pig Skins offers pork rinds and cracklins prepared and packaged in the Deep South and is produced by Rudolph Foods Company, Inc. Lee's Pig Skins is based in New Hebron and was founded in 1978 and incorporated in 1988.

The brand's tagline is “The Tastiest Pork Rind & Cracklin Snacks Between Texas and Tennessee.” In addition to its Lee's Pig Skins, Dabo's and Papa Tubs pork rinds, the snacks manufacturer produces pork strips, cracklins and washpot cracklins. Available flavors are Original, Hot, Hot Sweet and Salt & Vinegar. Hot & Spicy pork rinds address the industry's growing Hispanic food trend, overall address consumer interest in “healthy munchies” and low carb diet snacks – pork rinds contain zero carbohydrates and contain more protein than peanuts. Gaslamp Popcorn started making kettle corn in the historic Gaslamp district of San Diego in 1998. Gaslamp Popcorn now makes four flavors - Kettle Corn, Cinnamon Caramel, Olive Oil and Sea Salt, White Cheddar. Gaslamp Popcorn is 100% natural, Non-GMO, gluten-free. Gaslamp Popcorn is popped in California. All of Rudolph Foods brands are involved in event sponsorship, community initiatives and contest hosting in the USA. In 2010, the snack brand sponsored events including the Pork Rind Heritage Festival, where product samples and merchandise were handed out.

Southern Recipe maintains a strong online community of consumers, known as “the man cave”. This term stems from the brand's typical consumer demographic – the traditional, Southern working man – after which their website is named. Southern Recipe is involved in events and contests. In 2010, Southern Recipe hosted social media contest, Win The Ultimate Man Cave, as well as sponsored a local Ohio team's participation in the World Championship Punkin Chunkin competition. Pepe's El Original is involved in event sponsorship, such as Fiestas Patrias in Los Angeles, as well as hosting contests across the nation. In 2010, the Hispanic pork rind brand hosted its second contest – Mi Amor, Mi Chicharrones in celebration of National Hispanic Heritage Month. In 2010, Lee's Pig Skins sponsored several events in the – like the Smokin’ Pig Festival in Lake City, FL and the Cracklin Festival in Porte Barre, LA. In January 2011 Rudolph Foods declared "National Pork Rind Appreciation Day" to be observed each year on the same day as the NFL Super Bowl.

Rudolph Foods agreed to make charitable donations in return for online support of the campaign. Pork Rind Appreciation Day was launched as an annual event when thousands of consumers supported the idea that pork rinds deserve their own day. Ohio Governor John Kasich issued a letter of support of Pork Rind Appreciation Day on February 6, 2012; each year, Rudolph Foods and its family of brands, refreshes the campaign with a new consumer promotion, as well as, a renewed commitment to their charitable partner. Since 2012, Pork Rind Appreciation Day has supported Gridiron Greats Assistance Fund, a nonprofit organization that provides medical and financial assistance to former NFL players in dire need. Rudolph Foods Official Website Southern Recipe's Official Website Pepe's El Original Official Website Lee's Pig Skins Official Website Pork Rind Appreciation Day Official Website Gaslamp Popcorn Official Website Battle of the Pork Rind Heavyweights. Bloomberg Businessweek