A temporary water mount was prepared by mixing the dry powder with water and waiting until the material was fully hydrated.

SRM 3287 is a deeply colored purple-red powder with a strong tendency to clump together. The material includes a number of hard rounded tan inclusions to 0.75 mm (750 µm) long. These are intact or nearly intact small seeds. The remaining powder includes both irregular multicellular fragments, which are poorly visualized, and irregular fragments of single cells; much of this cellular debris is thin-walled and flimsy in appearance, and some is reddish. Fragments of the seed coat are present, often having a distinctly curved shape. These are composed of very thick-walled cells, somewhat pigmented, polygonal to angular, mostly in the range of 100–160 µm in the longest dimension. The combined thickness of the adjoining walls of two adjacent cells ranges from 30–50 µm (rarely as little as 20 µm); the cell walls are tan-colored with, usually, a reddish line at the interface between adjoining cell walls, which may be centrally positioned or near the inner surface of one cell wall. Flat multicellular fragments of the fruit wall are composed of reddish to pinkish polygonal cells, which range from 20–60 µm in the longest dimension. The cell walls of these pigmented cells are often somewhat thickened (a combined wall thickness of 3–6 µm, rarely to 9 µm) and pinkish in color.

Numerous sclereids are present in the material. Many sclereids are elongated, almost linear, usually 100–375 µm long and irregularly curved, consisting almost entirely of thick walls with little empty space inside the cell; these are seen singly or occasionally in clusters of 3–4. Other sclereids are broader for at least part of their length, ranging from irregularly angular to ovoid or broadly ellipsoid, and often contain a dark inclusion. These are most frequently 80–200 µm long but may exceptionally reach over 500 µm, and are found singly or rarely in sometimes large clusters. The walls of sclereids are clear and unpigmented; along each of the long walls, several small gaps in the thickened inner wall may be seen. In clusters of sclereids, these may be seen to be pit-pairs, matching corresponding thin spots in adjoining cell walls.

*National Institute of Standards and Technology Standard Reference Material 3287.