sentences:  The first was chemist Jacqueline Olin, then a researcher with the Smithsonian Institution, who in the 1970s conducted experiments which produced anatase at an early stage of a medieval iron-gall ink production process.Examination of her anatase by a colleague, mineralogist Dr Kenneth Towe, showed that it was very different from the neat, rounded crystals found in the Vinland Map and modern pigments.Towe himself, a clay specialist, briefly considered the possibility that the anatase could have come from clay, where it is present in trace amounts, but on checking McCrone's data found no significant traces of clay minerals.