Crystalline Morphology

Crystalline Morphology is the study of the external form of crystalline bodies as it is recorded, classified, and disputed within the Tower, together with the body of rulings governing which forms may be said to have one. It is distinguished from crystallography proper by a narrow but consequential reservation: the morphologist does not ask what a crystal is made of, only what shape it has been observed to hold, and for how long. The distinction is set out in Concordance 44-B, Annex 6, which states that "a form shall be reckoned morphological only where two surveyors, working from separate landings, record it independently and agree within one quarter of a grain."

The discipline is administered jointly by the Office of Lapidary Registry and the Bureau of Unstable Silhouettes, an arrangement no one has attempted to reform since Concordance 44-B itself, and which most practitioners describe as workable.

Origins

Crystalline Morphology emerged as a separate register following the Crystalline Resonance, when the forms catalogued in the affected galleries were found to have changed between successive inventories without any corresponding change in mass, colour, or lattice count. The Convergence Analysts cite the Resonance as the founding event of their discipline; morphologists prefer to cite it as the founding embarrassment, since it established that a shape could be logged, verified, and then not be there.

The first formal apparatus was the three-tier system of attunement grades, borrowed wholesale from survey practice and never returned. Under the system, forms are graded as attested, provisional, or retained-in-suspense. A form in the third grade is still entered in the register, but in a different ink.

The Morphological Register

The Register occupies four landings of Floor 5,441 and is maintained in eleven hands, of which ordinarily six are occupied. Entries are made in the order of the surveyor's arrival rather than the specimen's position, a practice defended in Directive 12.45 as preserving "the integrity of the walk." Attempts to reorder the Register alphabetically were abandoned in the winter of Tower Year 11,884 after the Clerks' Sorting Dispute, in which two scribes sorted the same landing twice in a single season and produced a pair of entries for a form since identified as a stray reflection.

The Register's holdings are not confined to minerals. Any body whose outer surface admits of a repeatable description may be entered, and the tendency of the Register to accumulate entries is a standing complaint of the Office of Lapidary Registry. The fourteen Avian-Silicate Hybrids of Gallery 7, Floor 5,442 were admitted on precisely this ground, over an objection that has never been formally withdrawn and is reprinted in each new recension of the Register's preface.

Named Forms and Their Troubles

Several forms in the Register have become fixed points of reference. The Sigma-Glass Pane is the standard worked example of a form that is stable in two dimensions and merely conventional in the third. The Ambivalent Prism is cited for its two mutually exclusive accepted profiles, and the Fluorite Lattice for the opposite case — a form so thoroughly attested that no surveyor has been able to produce a second independent reading of it, a circumstance that has kept it in the third grade since entry. The Counterfactual Crystals are entered under a separate heading altogether, as their morphology is not observed but inferred, and is therefore, in the Registrar's phrase, "not a shape but an argument."

Particular difficulty attaches to specimens whose form is maintained by prohibition rather than by structure. The class known as Prohibition by Lattice is morphologically legible only for as long as the relevant prohibition stands; when a Concordance lapses, the form relaxes, and the surveyor is left with an entry describing nothing. The Null Quartz presents the inverse problem, holding its form with such insistence that two surveyors have recorded it simultaneously from the same landing and been unable to agree on which of them was the second.

The Quiet Point Controversy

The central scholarly disagreement of the field concerns the so-called quiet point: the minimum interval at which a form may be said to persist rather than merely recur. Concordance 44-B fixes the interval at forty-one days. Concordance 61-C fixes it at nine, and adds, in a marginal note widely taken as deliberately provoking, that "the number forty-one has no morphological significance and is retained out of habit." Concordance 61-D does not address the matter, and is generally held to have made things worse.

"Where two Concordances speak to the same interval, the later shall govern; where they speak to different intervals, both shall be read aloud and the surveyor shall proceed as their conscience directs."

— Concordance 61-D, Annex 2

In practice most surveyors apply the forty-one-day rule to minerals and the nine-day rule to the Avian-Silicate Hybrids, on the grounds that the hybrids are unwell. The Bureau of Unstable Silhouettes has declined to rule on the practice, noting only that it is "consistent with the record and not with the text."

Instruments and Method

Observation is made by Lumino-Crystalline Sconces on the Provost's Ascent, where light is calibrated to 589 nm and may not be altered for any reason, including the comfort of visiting surveyors. The Crystalline Polyhedron of Autonomous Sorrow is the principal field instrument, and the Master of Crystalline Absence certification is required before a surveyor may handle one in the presence of a form already in the third grade, since the instrument will otherwise register the surveyor's own misgivings as a feature of the specimen.

Supporting apparatus includes the Resonant Argonium reference rods and the Translumine comparison slides, the latter held in a locked case on Floor 5,440 and signed out by the landing warden. Documentation follows the Morphology of Recursion where a form is anticipated before it is seen, and a Formal Variance Request (FVR-9k) is lodged where the anticipation itself has a discernible shape. The Appendix Fern is admitted to the Register only as a boundary case, and the less said of its fronds the better.

Surveyors are reminded that the Register is not a museum and that nothing entered in it may be removed from its landing for purposes of study. Forms entered in error are corrected in place, in the presence of the error, which is left where it is.