But while the official distinctions end there (aside from age designations like joven [young], reposado [rested], and anejo [old]), dramatic variability can exist even between 100% agave tequilas, and can be the result of dozens of factors including, just to name a few, the age of the agave plants, how they're roasted, and the soil in which their grown. Agave grown in the highlands, for example, in iron-rich red volcanic soil, tends to have a lower fiber density than other agave plants, which causes them to carry more moisture, providing more pronounced floral, fruity flavors. Lowlands agave (which still grow at a dizzying 3,800 feet above sea level) tends to carry more herbaceous, grassy flavors, largely a result of higher temperatures and more intense sunlight. This is where the French champagne sensibility comes in: Instead of sourcing one single variety of agave, Romero Mena made use of both highland and lowland varieties—roasting, juicing, fermenting, and distilling them entirely separately before blending the resulting spirits to perfection. To a sommelier, the idea might seem rather obvious, but Romero Mena's approach is a first in Mexico's tequila industry: No tequila on the mass market has ever used this model before.