1. A system for verifying an item in a package using a database, comprising: a database, wherein a package producer provides the database with an identifier for one or more items each of a type, wherein the package producer produces a package, where the package includes the one or more items each of the type with an associated one or more selected tag identifiers that are placed in a location on an item of the one or more items, wherein the identifier is based at least in part on a number encoded in a reflectance spectra of the one or more selected tag identifiers, wherein the number encoded in the reflectance spectra is determined by measuring the number and positions of the engineered reflectance peaks in the reflectance spectra of the one or more selected tag identifiers; and a verifier, wherein the verifier verifies the one or more items of the type by computing a marker identifier using 1) the associated one or more selected tag identifiers as detected using a spectral measurement and 2) a tag characteristic as detected using an imager, and matching the computed marker identifier with the identifier retrieved from the database.