Qenya
laka
much (abundant), a great quantity
laka malto
a great quantity of gold
laka malta
much (abundant) gold
There are more words but they are from Tolkien's earlier conceptional periods. Tolkien likely changed these words as he evolved the aesthetics and completeness of the languages. You may even find languages that Tolkien later rejected. Do not mix words from different time periods unless you are familiar with the phonetic developments.
Below: Tolkien's Late Period (1950–1973). These are from Tolkien's late conceptual period — his most settled forms of the languages. Prefer these over the earlier ones above when composing new text.
An adjective for “much” in the sense “much (abundant), a great quantity” in Demonstrative, Relative, and Correlative Stems (DRC) from 1948 (PE23/104). This adjective is used with a quantity rather than a countable set of things, as in i atan harya laca malta “the man has much gold”. It can used with a partitive genitive as well, in the singular or the plural as with laca malto “a great quantity of gold” or lacar malto “great quantities of gold”. Note that lacar in this example uses a noun plural rather than an adjective plural, because in this context it is being used substantively.
Conceptual Development: The Qenya Lexicon of the 1910s had the following words for “much”: ᴱQ. olda or olwa, olt, and olde which were respective adjective, noun and adverb, with olde also meaning “very” (QL/69). All were based on the early root ᴱ√OLO. A similar set of words for “much” appeared in the Early Qenya Grammar of the 1920s, adjective olya and adverb ole (PE14/48, 80), the latter also used as an augmentative with a longer form olōle (PE14/81). The forms ole and oléle were glossed “very” in the English-Qenya Dictionary also from the 1920s.