The original paper addresses this question thoroughly
> This omission stems in large part from uncertainty about whether prehistoric artifacts in the North American archaeological record can be confidently identified as dice. As DeBoer (Reference DeBoer2001:237) observed, “Identification of [ancient Native American] dice is problematic.” This article attempts to address this problem and dispel some of this uncertainty through a two-step process. First, it develops an objective, morphological test for identifying prehistoric Native American dice based on diagnostic attributes shared among 293 sets of historic Native American dice from across North America documented in Stewart Culin’s (Reference Culin1907) ethnographic compendium Games of the North American Indians. Second, it applies this test to trace the origins and antiquity of these artifacts in the published archaeological record. This analysis has yielded two key findings with intriguing implications.
> First, the evidence developed here suggests that Native American groups on the western Great Plains of North America were making two-sided dice (binary lots) and using them as randomizing agents in games of chance and for gambling by the closing centuries of the Pleistocene, no later than 12,000 years ago.
> Second, the evidence developed here shows that artifacts exhibiting the diagnostic attributes of historic Native American dice appear in archaeological assemblages from diverse groups throughout all periods of North American prehistory—from the Late Pleistocene / Early Holocene (aka the Paleoindian period), around 13,000–8000 years before the present (BP); through the Middle Holocene (aka the Archaic period), around 8000–2000 BP; and into the Late Holocene (aka the Late Prehistoric period), around 2000–450 BP
> METHODS
> The ethnographic dataset that forms the basis for the present study is Stewart Culin’s (Reference Culin1907) magnum opus Games of the North American Indians. This 809-page volume, containing 1,112 illustrations and 21 plates, catalogs the results of Culin’s nearly 14-year effort to compile a “classified and illustrated list of practically all the American Indian gaming implements in American and European museums, together with a more or less exhaustive summary of the entire literature of the subject” (Culin Reference Culin1907:30).
> His final report includes illustrations and descriptions of 293 unique sets of Native American dice from “130 tribes belonging to 30 linguistic stocks,” and it notes that “from no tribe [do dice] appear to have been absent” (Culin Reference Culin1907:48). In addition, Culin cites and quotes at length 149 ethnographic accounts of how these dice were used to power games of chance and for gambling. Based on this record, Culin suggested that “the wide distribution and range of variations in the dice games points to their high antiquity” (Reference Culin1907:48).
> A careful examination of the historic Native American dice documented by Culin reveals common diagnostic attributes that can form the basis of a morphological definition that can be applied to prehistoric artifacts. As illustrated and described by Culin—and discussed in more detail below—historic Native American dice share four key diagnostic attributes (Figures 2–4). First, they are two-sided objects made of bone or wood. Second, their two sides are distinguished by applied color or markings. Third, their appearance in section is either flat, plano-convex, concave-convex, or convex-convex (with the latter in all cases being a peach or plum stone; Culin Reference Culin1907:45–46, 51). Fourth, they are of a size and shape such that two or more can be held in the hand and cast onto a playing surface. Each of these attributes is considered below.
So TL;DR: they spent decades studying this to develop a morphological definition
Thank you for citing relevant passages. However, I find it all very unconvincing. The conclusion that these objects must have been dice is leaped to based on that very flexible morphological definition, and there is no consideration of alternative explanations. He even includes objects that don’t meet his own definition and still calls them “probable dice”!
Tally marked counters, coins, scrapers, prizers, jewellery, weapons, biface hand axes, totems, chisels, measuring devices… there is a huge array of possible tool types that meet this morphological definition.
They may well have been dice but the certainty expressed in the paper is unwarranted.
> This omission stems in large part from uncertainty about whether prehistoric artifacts in the North American archaeological record can be confidently identified as dice. As DeBoer (Reference DeBoer2001:237) observed, “Identification of [ancient Native American] dice is problematic.” This article attempts to address this problem and dispel some of this uncertainty through a two-step process. First, it develops an objective, morphological test for identifying prehistoric Native American dice based on diagnostic attributes shared among 293 sets of historic Native American dice from across North America documented in Stewart Culin’s (Reference Culin1907) ethnographic compendium Games of the North American Indians. Second, it applies this test to trace the origins and antiquity of these artifacts in the published archaeological record. This analysis has yielded two key findings with intriguing implications.
> First, the evidence developed here suggests that Native American groups on the western Great Plains of North America were making two-sided dice (binary lots) and using them as randomizing agents in games of chance and for gambling by the closing centuries of the Pleistocene, no later than 12,000 years ago.
> Second, the evidence developed here shows that artifacts exhibiting the diagnostic attributes of historic Native American dice appear in archaeological assemblages from diverse groups throughout all periods of North American prehistory—from the Late Pleistocene / Early Holocene (aka the Paleoindian period), around 13,000–8000 years before the present (BP); through the Middle Holocene (aka the Archaic period), around 8000–2000 BP; and into the Late Holocene (aka the Late Prehistoric period), around 2000–450 BP
> METHODS
> The ethnographic dataset that forms the basis for the present study is Stewart Culin’s (Reference Culin1907) magnum opus Games of the North American Indians. This 809-page volume, containing 1,112 illustrations and 21 plates, catalogs the results of Culin’s nearly 14-year effort to compile a “classified and illustrated list of practically all the American Indian gaming implements in American and European museums, together with a more or less exhaustive summary of the entire literature of the subject” (Culin Reference Culin1907:30).
> His final report includes illustrations and descriptions of 293 unique sets of Native American dice from “130 tribes belonging to 30 linguistic stocks,” and it notes that “from no tribe [do dice] appear to have been absent” (Culin Reference Culin1907:48). In addition, Culin cites and quotes at length 149 ethnographic accounts of how these dice were used to power games of chance and for gambling. Based on this record, Culin suggested that “the wide distribution and range of variations in the dice games points to their high antiquity” (Reference Culin1907:48).
> A careful examination of the historic Native American dice documented by Culin reveals common diagnostic attributes that can form the basis of a morphological definition that can be applied to prehistoric artifacts. As illustrated and described by Culin—and discussed in more detail below—historic Native American dice share four key diagnostic attributes (Figures 2–4). First, they are two-sided objects made of bone or wood. Second, their two sides are distinguished by applied color or markings. Third, their appearance in section is either flat, plano-convex, concave-convex, or convex-convex (with the latter in all cases being a peach or plum stone; Culin Reference Culin1907:45–46, 51). Fourth, they are of a size and shape such that two or more can be held in the hand and cast onto a playing surface. Each of these attributes is considered below.
So TL;DR: they spent decades studying this to develop a morphological definition
https://www.cambridge.org/core/journals/american-antiquity/a...